OPINION OF THE COURT
Milla Karkkainen filed a Petition for Return of Child under the Hague Convention *285 on the Civil Aspects of International Child Abduction, Oct. 25, 1980, T.I.A.S. No. 11670, 19 I.L.M. 1501 (“Hague Convention”). Karkkainen alleged that her ex-husband, Vladimir Kovalchuk, and his current wife, Julie d’ltri (collectively, the “Respondents”), wrongfully retained her daughter, Maria Kovalchuk, when she was eleven years old. The District Court denied the petition, holding that there was no wrongful retention because Maria’s habitual residence was the United States. Karkkainen appeals this decision, arguing that Maria is habitually resident in Finland. Although this is a close case, we believe that, prior to her retention, Maria acclimatized to the United States and that there was a degree of settled purpose from her perspective to remain in this country. The existence of shared parental intent to permit Maria to choose her country of residence bolsters this conclusion. Thus, we agree with the District Court’s finding that Maria is a habitual resident of the United States and will affirm.
I. Facts and Procedural History
Maria was born on April 25, 1992 in Russia. Her parents, Milla Karkkainen and Vladimir Kovalchuk, were married at the time and remained so until 1997. After their divorce, Karkkainen and Kovalchuk agreed that Maria would live with her mother in Finland.
Both Karkkainen and Kovalchuk remarried after their split. Karkkainen married Kimmo Karkkainen in January 1998, and Kovalchuk married Julie d’ltri in September 2000. Kovalchuk and d’ltri saw Maria periodically, either by traveling to Europe or by bringing her for.visits to the United States. In 2000, however, Maria was unable to obtain a tourist visa for a visit to the United States due to the concerns of the United States Consulate in Finland about Maria’s custody status.
As part of their effort to obtain a visa for Maria to visit the United States, Kovalchuk and Karkkainen signed a Stipulation in Custody in December 2000 that clarified their custody arrangement. The Stipulation provided, inter alia, that Karkkainen “shall have primary physical custody of [Maria], including the right of the child’s residence in Finland, which for purposes of The Hague Convention on the Civil Aspects of Child Abduction, shall be considered the child’s ‘habitual residence.’ ” (Stipulation in Custody ¶ 5 at App. 503.) The parents continued to share legal custody of Maria such that both had “the right and responsibility to make major decisions affecting ... [her] best interest.” (Stipulation in Custody ¶ 3 at App. 503.) The terms of the Stipulation required that it be filed with the Court of Common Pleas of Allegheny County, Pennsylvania. Though the Stipulation was signed by a common pleas judge, the parties never actually filed it with the court. The record reflects that the primary purpose of the Stipulation in Custody was to secure Maria’s tourist visa.
Despite these efforts to clarify Maria’s custody status, Maria was unable to obtain a visa to visit the United States. In February 2002, the parties began discussions about making Maria a permanent resident of the United States for immigration purposes, which would dispense with the need for a tourist visa. In March 2002, Karkkainen granted permission for Maria to become a permanent American resident in a signed and notarized document. It was Karkkainen’s understanding at that time that she would not lose any custody rights over her daughter if she were made a permanent resident of the United States, but that the change in immigration status would give Maria the right to remain in the United States indefinitely. Maria was granted an immigrant visa in September *286 2002 and she officially became a permanent resident of the United States when she visited the country in October 2002. She also visited the United States in December 2002 during the Christmas holiday and over her Easter break in April 2003.
During the winter of 2002 and spring of 2003, Maria, her parents, and her stepparents began to plan for Maria to make a longer visit to the United States. The parties agreed that she would spend the entire summer here with her father and d’ltri. In addition, Maria began increasingly to express her preference to move permanently to the United States. Maria had a conversation in May 2003 with her mother and stepfather in which she stated that she wanted to live with her father. Maria’s stepfather told her that she was free to make that decision. When Karkkainen did not disagree with this statement, Maria was left with the impression that she had been given permission to move permanently to the United States if she wished. After this conversation, Maria said goodbye to her teacher, Tuula Merenheimo, and to several friends, telling them that she was moving to the United States. As a parting gift, Merenheimo gave Maria the books that she would have used during the next school year in Finland. These books were usually kept by the teacher during the summer and handed out at the beginning of the academic year.
Several events reinforced Maria’s belief that she would be permitted to move to the United States permanently. Milla and Kimmo Karkkainen helped Maria apply to a private American school for the fall semester of 2003 by faxing her academic transcripts to the school. Maria heard her mother tell her grandmother on the telephone that Maria was moving to the United States. And Karkkainen let Maria travel to the United States on June 6, 2003, moments after Maria told Karkkainen that she was unsure she would return to Finland at the end of the summer.
The central factual dispute of this case is what the understanding of the parties was at the time Maria came to the United States. The Respondents claim that the parties agreed that the summer would be a trial period during which Maria would decide whether she wanted to move to the United States permanently. Karkkainen argues that she never granted permission for Maria to live in the United States indefinitely and that she expected Maria to return to Finland on August 10, 2003.
The record reflects that Maria is both mature and intelligent for her age. An expert in teaching and training children in the performing arts testified that Maria is “a very focused, gifted, talented and ... creative child” with particularly strong skills in photography and drawing. An independent child psychologist found that Maria was “uniquely talented and highly intelligent,” an impression the District Court echoed after hearing Maria’s testimony. Maria could communicate well in Finnish, English, and Russian, and had extensive experience traveling in Europe and the United States for visits with her father. She was, in short, much more experienced and mature than the average eleven year old when she came to the United States on June 6, 2003.
During the summer of 2003, Maria took academic classes, studied photography, traveled in the United States, and cultivated her relationships with d’ltri and d’ltri’s family. In addition, Maria was admitted to a private American school named The Ellis School, where she enrolled to attend in the fall. When Maria did not return to Finland in August 2003, Karkkainen filed a Petition for Return under the Hague Convention. The District Court determined that Maria had become acclimatized during *287 her stay in the United States prior to the date of her retention. Accordingly, the Court found that Maria was a habitual resident of the United States and refused to return her to Finland.
The District Court had subject matter jurisdiction under 28 U.S.C. § 1331 and 42 U.S.C. § 11603(a). We have appellate jurisdiction under 28 U.S.C. § 1291.
II. The Legal Framework of the Hague Convention
The two main purposes of the Hague Convention are “to ensure the prompt return of children to the state of their habitual residence when they have been wrongfully removed,” Hague Convention, pmbl., and “to ensure that rights of custody and of access under the law of one Contracting State are effectively respected in the other Contracting States,”
id.,
art. 1. The Convention’s procedures are not designed to settle international custody disputes, but rather to restore the status quo prior to any wrongful removal or retention, and to deter parents from engaging in international forum shopping in custody cases.
Baxter v. Baxter,
Any person seeking the return of a child in the United States may commence a civil action under the Convention by filing a petition in a court of the jurisdiction in which the child is located. 42 U.S.C. § 11603(b). To obtain an order for the child’s return under the Hague Convention, the petitioner bears the burden of proving by a preponderance of the evidence that the removal or retention was wrongful under Article 3. 42 U.S.C. § 11603(e)(1)(A). Under Article 3 of the Hague Convention, the removal or retention of a child is “wrongful” where:
a. it is in breach of rights of custody attributed to a person, an institution or any other body, either jointly or alone, under the law of the State in which the child was habitually resident immediately before the removal or retention; and
b. at the time of removal or retention those rights were actually exercised, either jointly or alone, or would have been so exercised but for the removal or retention.
Hague Convention, art. 3.
A petitioner cannot claim that the removal or retention of a child is “wrongful” under the Hague Convention unless “the child to whom the petition relates is ‘habitually resident’ in a State signatory to the Convention and has been removed to or retained in
a different State.
”
Gitter v. Gitter,
Thus, we have noted that wrongful removal or retention claims under Article 3 of the Convention typically raise four questions: (1) When did the removal or retention at issue take place? (2) Immediately prior to the removal or retention, in which state was the child habitually resident? (3) Did the removal or retention breach the rights of custody attributed to the petitioner under the law of the habitual residence? (4) Was the petitioner exercising those rights at the time of the removal or retention?
See Baxter,
Even when a court finds wrongful removal or retention, it is not necessarily required to return a child to its habitual residence. After a petitioner demonstrates wrongful removal or retention, the burden shifts to the respondent to prove an affirmative defense against the return of the child to the country of habitual residence.
Baxter,
III. The District Court’s Evidentiary and Factual Rulings
Though the fundamental issue in this appeal is whether the District Court correctly determined Maria’s habitual residence, Karkkainen also contends that the District Court erred in several evidentiary rulings and in its fact-finding. Because these rulings formed the basis for the District Court’s holding that Maria was not wrongfully retained, we take them up before turning to the merits of Karkkainen’s claim under Article 3 of the Convention. 1
We review the District Court’s determinations concerning the admissibility of evidence for abuse of discretion.
Forrest v. Beloit Corp.,
Karkkainen claims that the District Court abused its discretion by appointing an expert to evaluate Maria’s level of maturity that lacked sufficient experience in “parental alienation syndrome.” Karkkainen argues that one of the central themes of her case was that Maria had been alienated from her mother by the Respondents and that the District Court therefore should not have considered Maria’s desire to move to the United States permanently. As evidence of Maria’s alienation, Karkkainen cites an instance in which Maria called her mother “aunt.” However, as the District Court noted, Karkkainen raised the claim of Maria’s alienation only as a way to rebut the Respondents’ affirmative defenses. Because the District Court ruled that the United States was Maria’s habitual residence, Respondents’ affirmative defenses were not at issue and any lack of knowledge on the part of the expert about “parental alienation syndrome” was irrelevant.
The District Court heard testimony from two witnesses that Karkkainen argues should not have testified. The cus
*289
todian of records from The Ellis School testified as to whether the school relied on documents sent by Maria’s Finnish teacher for her admission. Though Karkkainen contends that this testimony constituted unfair surprise, the records custodian was listed as a witness on the witness list. The District Court did not abuse its discretion in permitting her to testify as to factual matters about which she had personal knowledge. Karkkainen also argues that Maria should not have been permitted to testify. However, the District Court held, based on expert evidence, that Maria was mature enough to testify. Because Maria’s perspective was central to the question of her habitual residence under the Hague Convention, see
Feder,
The District Court admitted testimony about whether Maria was “well-settled.” Karkkainen argues that the “well-settled” defense of Article 12 of the Hague Convention is inapplicable in this case and that the District Court should have rejected testimony as to this issue. The District Court reserved judgment on whether the well-settled defense applied and stated that it would consider the testimony only if the defense later became relevant. There is no evidence that the District Court used such testimony to reach its decision on habitual residence, the only subject of its holding. Likewise, we reject Karkkainen’s claim that the District Court improperly permitted testimony regarding Maria’s best interests. Karkkainen points to no specific instances in which the District Court permitted such testimony, and we have found none within the record. We also conclude that the District Court admitted hearsay testimony only under the exceptions of the Federal Rules and properly limited its use. Thus, we find no abuse of discretion on these points.
Finally, Karkkainen argues that the District Court erred in finding that the parties agreed to allow Maria to choose whether she would live in the United States indefinitely or return to Finland at the end of the summer of 2003. We must review this factual finding for clear error.
Baxter,
The record supports the District Court’s conclusion that the parties agreed when Maria left for the United States in June 2003 that she would choose where she would reside after the summer. At an interview at the American Embassy in Helsinki in September 2002, d’ltri explained to a consular officer that Maria would have the option of remaining in the United States after her visit in the summer of 2003. Karkkainen was present during the conversation and did not object to the proposed plan. Email exchanges and multiple discussions between the parties leading up to Maria’s 2003 trip to the United States also suggested that Karkkainen agreed Maria was “free to go” to the United States indefinitely. In addition, Karkkainen aided the Respondents in their efforts to place Maria in The Ellis School for the Fall 2003 school semester and never contacted the school to indicate that she did not wish Maria to attend. Indeed, on the very day Maria left for the United States, she and her mother discussed the possibility that Maria would not return to Finland at the end of the sum *290 mer. Taken together, this and other evidence in the record supports the District Court’s finding that Karkkainen, the Respondents, and Maria all understood that Maria would have the choice of remaining in the United States and that she would not necessarily return to Finland in August 2003.
At the same time, there is evidence in the record that could support a different conclusion. For example, Karkkainen never expressly gave permission for Maria to attend school in the United States. Moreover, the Respondents stated in a January 2003 email that it was their understanding that Maria would return to Finland in August 2003. The fact that Maria had a round-trip ticket with which she could return to Finland on August 10, 2003 may also suggest that the parties did not intend Maria to remain in the United States indefinitely. Despite such evidence, we will not set aside the District Court’s finding given our deferential clear error standard.
IV. Date of Retention
Having resolved Karkkainen’s evidentiary and factual objections, we must determine when the alleged wrongful retention occurred so as to establish the relevant date of Maria’s habitual residence for purposes of the Hague Convention. The District Court held that the date of retention was August 28, 2003, the date on which Karkkainen filed her petition for Maria’s return. Prior to that time, the Court found that there was an ongoing dispute between the parties about whether the agreement to allow Maria to stay permanently in the United States remained in effect. Once Karkkainen filed the petition for Maria’s return, she unequivocally signaled her opposition to Maria’s presence in the United States. After that date, there was no doubt that Maria remained with her father against her mother’s wishes and was therefore retained.
See Slagenweit v. Slagenweit,
Karkkainen argues that August 10, 2003, not August 28, 2003, is the proper date of retention. This was the date of Maria’s return airline ticket to Finland and the date after which Kimmo Karkkainen indicated in a July 2003 email to the Respondents that Maria’s presence in the United States would constitute kidnapping. Karkkainen argues that there is no legal basis for setting the date of retention as the day on which she unequivocally communicated her opposition to Maria’s presence in the United States and that, in any event, she had clearly communicated her opposition prior to August 28, 2003.
This case does not require us to decide whether a child is not retained under the Convention until a parent unequivocally communicates his or her desire to regain custody. We assume that this standard applies, but hold that it was clearly erroneous for the District Court to find that Karkkainen had not clearly communicated her opposition to Maria’s presence in the United States until she filed the petition for return. There is unrebutted evidence in the record showing that, by mid-July 2003, Karkkainen had withdrawn her consent to have Maria remain in the United States beyond August 10, 2003 and that the Respondents were fully aware of this. Neither the District Court nor the Respondents pointed to anything in the record that suggests there was confusion about Karkkainen’s opposition after mid-July 2003, and we have found no such evidence ourselves. Under these circumstances, we must set aside the District Court’s factual
*291
finding and accept as the date of retention August 10, 2003, prior to which it is undisputed that Maria was present in the United States with Karkkainen’s permission.
See Toren v. Toren,
V. Habitual Residence
Whether the Respondents wrongfully retained Maria under the Hague Convention will be determined by where Maria habitually resided immediately prior to her alleged wrongful retention on August 10, 2003. If we find Finland was Maria’s habitual residence on that date, we must also find that her retention in the United States was wrongful; if we conclude that Maria was a habitual resident of the United States, her retention here would not be wrongful under Article 3 of the Convention.
See Gitter,
A. Legal Standards for Habitual Residence
The Convention does not specifically define the term “habitual residence.” Though the Courts of Appeals have employed slightly different tests for habitual residence, each test has in common the goal of determining where a child’s home is at the time of removal or retention. These tests facilitate the primary objective of the Hague Convention: to ensure stability in a child’s family and social environment. See Elisa Perez^-Vera, Explanatory Report ¶¶ 11, 24, 72, in 3 Hague Conference on Private International Law, Acts and Documents of the Fourteenth Session, Child Abduction 426 (1982) (“Perez-Vera Report”). 2
The inquiry into a child’s habitual residence is a fact-intensive determination that cannot be reduced to a predetermined formula and necessarily varies with the circumstances of each case.
Whiting,
at 546. This is especially true in cases such as this one, where the petitioning parent initially agreed to allow the child to stay abroad for an indefinite duration, but subsequently had second thoughts about that decision.
Mazes,
We have stated that a child’s habitual residence is “the place where he or she has been physically present for an amount of
*292
time sufficient for acclimatization and which has a ‘degree of settled purpose’ from the child’s perspective.”
Feder,
Though we examine acclimatization and settled purpose “from the child’s perspective,”
Feder,
In addition to considering how parental intent affected a child’s perspective, we must also give some independent weight to “the parents’ present,
shared
intentions regarding their child’s presence” in a particular place.
Feder,
It is obvious based on these standards that Maria was a habitual resident of Finland prior to her arrival in the United States on June 6, 2003. She lived in that country for years and was acclimatized to her environment there in every way. In addition, Finland was the country that Maria’s parents had set as her habitual residence in their Stipulation in Custody. The question before us, then, is whether Maria’s habitual residence changed from Finland to the United States prior to the retention date.
B. The Stipulation in Custody
Before applying these standards to the instant case, we address Karkkainen’s claim that the Stipulation in Custody prevented a change in Maria’s habitual residence, as it remained binding and rendered Maria habitually resident in Finland on the retention date. The District Court disagreed with this argument and found that the parties had modified the Stipulation by developing a shared intention that *293 Maria would be permitted to decide during the summer of 2003 whether she wished to move to the United States or return to Finland. Because we will not set aside the District Court’s finding that the parties agreed Maria would decide for herself whether to return to Finland, we must determine whether this shared intention effectively modified the Stipulation in Custody.
Though it was signed by a common pleas judge, the Stipulation in Custody was never filed with the Court of Common Pleas of Allegheny County, as its terms required. Consequently, it is an informal custody agreement under Pennsylvania law, not a binding court order.
Witmayer v. Witmayer,
Furthermore, the Stipulation was prepared for the express purpose of obtaining a tourist visa for Maria. Maria has since become a permanent legal resident of the United States, making a tourist visa unnecessary for her to visit or remain in this country. Because Maria’s immigration status was critical to the factual context in which the parties drafted the Stipulation, this change buttresses our conclusion that the instant case involves different circumstances from those present when the parties entered the Stipulation and that the Stipulation’s lasting effectiveness is suspect. Id. We therefore afford no weight to the provision of the Stipulation in Custody that sets Finland as Maria’s habitual residence.
C. Acclimatization and Degree of Settled Purpose
To determine whether Maria’s habitual residence changed from Finland to the United States, we first consider whether she acclimatized to the United States prior to the date of retention and whether there was a degree of settled purpose from her perspective to remain in this country beyond August 10, 2003.
Whiting,
Applying the lessons of such cases to the circumstances before us, there is evidence in the record that Maria acclimatized herself to the United States during the summer of 2003. She enrolled in The Ellis School and took summer classes
*294
to prepare for her attendance there in the fall. She also took photography classes that summer, traveled in the country, and developed relationships with d’ltri and her family that she had established during previous visits to the United States in October 2002, December 2002, and April 2003. We view these events in the context of record evidence that Maria is “uniquely talented and highly intelligent,” an experienced traveler with strong English skills, and mature for her age. Taken together, these factors suggest that Maria “form[ed] meaningful connections with the people and places she encounter[ed]” in the United States and was therefore acclimatized prior to the date of her retention.
Whiting,
Furthermore, there is evidence in the record that Maria abandoned Finland as her habitual residence. When Maria came to the United States in June 2003, she brought more personal belongings with her than usual, in anticipation that she would remain here after the summer.
See Silverman,
There are also factors that weigh against a finding of acclimatization. “Habitual residence may only be altered by a change in geography and passage of time,”
Silverman,
As stated above, the intentions of a child’s parents “affect[ ] the length of time necessary for a child to become habitually resident, because the child’s knowledge of these intentions is likely to color its attitude to the contacts it is making.”
Mozes,
There is considerable evidence that the agreement between Maria’s parents “colored her attitude” towards her visit to the United States during the summer of 2003. Maria thought when she arrived that she would be permitted to choose, before the end of the summer, the country in which she would reside permanently. In multiple conversations with parents and stepparents, Maria expressed her desire to pick her residence. She indicated to her friends and teacher prior to leaving Finland that her parents would allow her to choose where she would live after the sum *295 mer of 2003. Furthermore, Maria told her mother on the day that she was leaving for the United States that she was not sure she would return. The fact that Maria believed that she controlled her own destiny influenced her entire experience in the United States prior to her retention here. Indeed, Maria strongly suspected even before she arrived that she would choose to remain here. Under these circumstances, less time was required for Maria to acclimatize and demonstrate a degree of settled purpose to stay in the United States than would normally be the ease.
We are presented with a unique fact pattern, in that Maria’s parents agreed in June 2003 that she possessed “the material and psychological wherewithal” to decide where she would reside.
Mozes,
Karkkainen argues that the agreement among the parties was nullified once she withdrew her consent that Maria could remain with her father beyond August 10, 2003, which the record shows occurred in mid-July. One could hardly question the proposition that Karkkainen’s protests changed the intent of the parties as it existed in June 2003, but this misses the point. “Habitual residence is intended to be a description of a factual state of affairs, and a child can lose its habitual attachment to a place even without a parent’s consent.”
Mozes,
Though the relatively short period of time Maria was present in the United States makes it a close question, we hold that Maria was acclimatized to the United States on the date of her retention and that her conduct demonstrated a degree of settled purpose to remain here. We base this conclusion on the specific facts and circumstances before us,
Whiting,
D. Shared Intent
In addition to considering habitual residence from Maria’s perspective,
Feder
requires that we give independent weight to her parents’
shared
intent.
We give somewhat less weight to shared parental intent in cases involving older children, like Maria, who have reached an age where they are capable of becoming “firmly rooted” in a new country.
Holder,
Our cases have not established with any precision how a court should balance shared parental intent against evidence of acclimatization and settled purpose from the child’s perspective where the child is
not
very young. As the Court of Appeals for the Ninth Circuit noted in
Mozes,
per
*297
haps the most difficult question in this regard is “when evidence of acclimatization should suffice to establish a child’s habitual residence” in the face of “uncertain or contrary parental intent.”
Here, because both shared parental intent and acclimatization support a finding that Maria was habitually resident in the United States, we need not decide how we would weigh these factors against each other if they conflicted, which was the focus of
Mozes.
Accordingly, we note only that, consistent with our instruction in
Feder,
courts must consider “the parents’ present, shared intentions” as part of the habitual residence analysis.
When a removal or retention is in accordance with the shared intent of both parents, there is no unilateral action, and therefore no harm for a court to remedy under the Hague Convention.
See Toren,
In summary, though we find it to be a close question, we agree with the District Court’s holding that Maria acclimatized to the United States prior to her retention and that her conduct demonstrated a degree of settled purpose to remain here.
*298 This weighs in favor of a finding that Maria was habitually resident in the United States on the retention date. The shared parental intent that Maria would choose her country of residence during the summer of 2003 further bolsters this conclusion. Consequently, we hold that Maria is a habitual resident of the United States and that she was not wrongfully retained under Article 3 of the Hague Convention.
For the foregoing reasons, we will affirm the District Court.
Notes
. Karkkainen also argues that the District Court made several erroneous procedural rulings by (1) entering an order modifying an existing child custody order, (2) denying appellant’s motion to strike appellee's late-filed answer and affirmative defenses, (3) allowing counsel for the child to exceed her authority, (4) denying appellant’s motion to correct the record, and (5) causing the proceedings below, and the resolution thereof, to be delayed excessively. Karkkainen provides no authority whereby we would reverse the District Court's order due to these alleged errors and, more importantly, we find these procedural arguments lacking in merit.
. Elisa Perez-Vera was the official Hague Conference Reporter, and her report is generally recognized as "the official history and commentary on the Convention.” Legal Analysis of the Hague Convention,
. Karkkainen characterizes the instant case differently as one in which "the child's initial move from an established habitual residence was clearly intended to be for a specific, limited duration.”
Whiting,
