Linda Isbell, individually and as next friend of Jordan Isbell and Kaitlyn Isbell, Stephen Ryan, and Charlotte Ryan appeal the district court’s grant of summary judgment to American National Property and Casualty Company (“ANPAC”) and American National General Insurance Company (“ANGIC”) (collectively, “American National”). The issue is whether a homeowner’s policy provides coverage for a lawsuit seeking damages caused by a parent’s negligent failure to warn of her minor son’s propensity to commit acts of sexual molestation against other minor children. Because we conclude the facts alleged in the negligence action do not constitute an occurrence as defined by the homeowner’s policy, we AFFIRM.
I
The facts in this case are essentially undisputed. MFI is the son of Charlotte Ryan and her first husband, Michael G. Isbell. MFI lived with his mother and her second husband, Stephen Ryan, during most of the year, but regularly visited and spent a part of each summer with his father, Michael Isbell, his second wife, Linda Isbell, and their two minor daughters. In 1995, MFI stayed with the Isbells for part of the summer. In June 1995, the Isbell daughters told their mother that their half-brother had repeatedly sexually molested and abused them. The Isbells reported the incidents to the appropriate authorities, and MFI was charged with two counts of aggravated sexual assault. The court found that MFI committed the charged conduct.
Linda Isbell, individually and as next friend of her two minor daughters, filed suit in state court against Charlotte Ryan, individually and as next friend of her minor son MFI. In her petition, Linda Isbell alleged that Charlotte Ryan breached her duty to warn the Isbells of MFI’s propensity to molest children. Specifically, she alleged that Charlotte Ryan was aware of MFI’s proclivities from an investigation of MFI conducted by Child Protective Services (CPS) after MFI was accused of sexually molesting- a male cousin in 1993-1994. CPS found good cause to believe the sexual and physical abuse had occurred, referred the Ryans to appropriate services, and obtained an agreement from the alleged victim’s mother not to allow MFI access to his cousin. According to Linda Isbell, Charlotte Ryan did not convey to the Isbells the result of the CPS investigation, did not apprize them of other accusations against MFI of sexual impropriety, did not warn of MFI’s proclivities for sexual improprieties with other children, and did not warn that MFI was a danger to minor children. 1
At the time the events alleged in Linda Isbell’s negligence action took place, Charlotte and Stephen Ryan were insured by a Texas Standard Homeowner’s Policy (“the Policy”) issued by ANGIC. 2 ANGIC filed a declaratory judgment action in federal court against Stephen and Charlotte Ryan seeking a declaration that it had no dutyto defend the Ryans in the state court action under the Policy, nor any obligation to pay or indemnify them for any damages reeov- *323 ered by Linda Isbell. Thereafter, Linda Isbell instituted a declaratory judgment action in state court against ANGIC and ANPAC for a declaration of her rights with respect to the Ryans’ Policy. Linda Isbell’s action was removed to federal court, and by agreement of the parties, consolidated with ANGIC’s action. The parties agreed to realign themselves in the consolidated action, with ANGIC and AN-PAC as plaintiffs and Linda Isbell and the Ryans as defendants.
In the consolidated action, the parties cross-moved for summary judgment. The district court granted ANGIC’s and AN-PAC’s motion for summary judgment and denied Linda Isbell’s and the Ryans’ motion. The district court issued a memorandum and opinion holding that the facts alleged in Linda Isbell’s negligence action against Charlotte Ryan did not constitute an “occurrence” as required by the Policy as a prerequisite to coverage. Alternatively, the district court held the sexual molestation committed by MFI to be excluded under the Policy’s intentional acts exclusion. As a result, the district court held that neither ANGIC nor ANPAC had a duty to defend nor any obligation to pay or indemnify the Ryans under the Policy. Linda Isbell and the Ryans now appeal.
II
We review a district court’s grant of summary judgment de novo.
McClendon v. City of Columbia,
Texas rules of contract interpretation control in this diversity case.
Bailey,
A
Linda Isbell and the Ryans contend that American National has a duty to defend and potentially a duty to indemnify Charlotte Ryan in Linda Isbell’s state action against her. Under Texas law, the
*324
duty to defend and the duty to indemnify are separate and distinct obligations.
Am. Alliance Ins. Co. v. Frito-Lay, Inc.,
We determine an insurer’s duty to defend from the factual allegations of the plaintiffs petition in the underlying action.
Argonaut S.W. Ins. Co. v. Maupin,
By the terms of the Ryans’ Policy, in order for coverage to exist and American National to have a duty to defend, the underlying action must allege damages caused by an “occurrence.” The Policy provides liability coverage, in relevant part, as follows:
Coverage C (Personal Liability)
If a claim is made or suit is brought against an insured for damages for bodily injury or property damage caused by an occurrence to which this coverage applies, we will: (1) Pay up to our limit of liability for damages for which the insured is legally liable; (2) Provide a defense at our own expense by counsel of our choice even if the suit is groundless, false or fraudulent. We may investigate and settle any claim or suit that we decide is appropriate.
The Policy defines an “occurrence” as “an accident, including exposure to conditions which result in bodily injury or property damage during the policy.” Athough the Policy does not define the term “accident,” Texas case law defines it as “an unexpected happening without intention or design.”
Allen v. Auto. Ins. Co.,
Linda Isbell and the Ryans do not dispute that MFI’s sexual molestation of the Isbell daughters was intentional and thus not an accident. They concede that, from *325 the standpoint of MFI, it did not constitute an occurrence within the meaning given by the Policy. They contend instead that Charlotte Ryan’s negligent acts causing the Isbell daughters’ injuries must be considered separately from MFI’s intentional acts.
To support this claim, Linda Isbell and the Ryans focus on the significance of the Policy’s severability clause. The Policy’s severability clause reads: “This insurance applies separately to each insured.” Linda Isbell and the Ryans argue that the severability clause modifies the definition of occurrence so that the determination of whether an event constitutes an “occurrence” must be made from the perspective of the insured being sued. 3 Because MFI’s acts were “unexpected and without design” from the standpoint of Charlotte Ryan, they argue that they satisfy the threshold requirement of an “occurrence” for coverage purposes. Thus, they conclude, Coverage C of the Policy obligates American National to defend Charlotte Ryan in Linda Isbell’s negligence action.
We have held that, under Texas law, “where a third-party’s liability is related to and interdependent on other tortious activities, the ultimate issue [in determining coverage] is whether the underlying tortious activities are encompassed within the definition of ‘occurrence.’ ”
Am. States Ins. Co. v. Bailey,
B
Linda Isbell and the Ryans contend that even if these cases correctly state Texas law, the severability clause in the Ryans’ Policy changes the result in this case. They rely mainly on three cases interpreting Texas law to support this view. We are not persuaded, however, that any of *326 these cases control the outcome of this case.
First, Linda Isbell and the Ryans state that the holding in
Commercial Standard Insurance Co. v. American General Insurance Co.,
Commercial Standard is distinguishable from the case now before us. In this case, we must determine the effect of the sever-ability clause, if any, on the definition of an “occurrence” under the Policy. Unlike the exclusion at issue in Commercial Standard, which was defined with respect to “the insured,” an occurrence is defined in the Ryans’ Policy with respect to an event. The definition of occurrence does not contain any language referencing “the insured” to which the severability clause can be linked. Instead, it simply defines a set of facts, namely, an accident. As a result, Linda Isbell’s and the Ryans’ reliance on Commercial Standard is misplaced.
Second, Linda Isbell and the Ryans rely on our decision in
Western Heritage Insurance Co. v. Magic Years Learning Centers & Child Care, Inc.,
Linda Isbell and the Ryans acknowledge this difference between Magic Years’s policy and the Ryans’ Policy. Still, they argue that our alternative holding in
Magic Years
that the sexual harassment would fall within the definition of occurrence even in the absence of the special endorsement should control the outcome of this case. We are not persuaded that this point in
Magic Years
should be accorded such weight. We have repeatedly criticized and declined to follow this aspect of
Magic Years
as unexplained and inconsistent with Texas precedent.
See N.Y. Life Ins. Co. v. Travelers Ins. Co.,
Finally, Linda Isbell and the Ryans suggest that the Texas Court of Appeals decision in
Walker v. Lumbermens Mutual Casualty Co.,
While none of these cases addressed the significance of a severability clause for determining whether a complaint alleges an occurrence, two recent Texas Court of Appeals eases have reached this issue. In
King v. Dallas Fire Insurance Co.,
the sole issue on appeal was whether Dallas Fire had a duty to defend King in a personal injury suit arising from an assault committed by one of King’s employees.
*328
Another division of the Texas Court of Appeals applied similar reasoning a few months later in
Folsom Investments, Inc. v. American Motorists Insurance Co.,
Although King and Folsom both involved an employer’s liability coverage with respect to the intentional torts of an employee, we find their reasoning applicable to this case. Like Folsom and King, Charlotte Ryan faces a claim for damages caused by the intentional tort of another as a result of her own negligence with respect to the tort’s commission. In the absence of MFI’s molestation of the Isbell daughters, there would be no claim against Charlotte Ryan. We find no principled reason for affording the severability clause in the Ryans’ Policy greater effect than the severability clauses at issue in King and Folsom simply because this case does not involve an employer and an employee.
Linda Isbell and the Ryans urge us to depart from
King, Folsom,
and the Fifth Circuit cases upon which they rely, because those cases misstate Texas law. They contend that, in the absence of clear precedent from the Texas Supreme Court, we should rely on
Agoado Realty Corp. v. United Int’l Ins. Co.,
We do not find
Agoado
persuasive in this case. Under the
Erie
doctrine, we are bound in diversity cases to apply the substantive law of the forum state as interpreted by the state’s highest court.
Ladue v. Chevron U.S.A., Inc.,
C
Finally, Linda Isbell and the Ryans argue that the Policy’s definition of occurrence is at the very least ambiguous, and thus should be read in favor of coverage. Specifically, they argue that by interpreting the threshold requirement of an occurrence to exclude claims related to and interdependent on the intentional conduct of others, we render the Policy’s intentional acts exclusion and the severability clause void. As the Ryans’ Policy was originally issued, the intentional acts exclusion excluded from coverage “bodily injury ... which is caused intentionally by or at the direction of an insured.” The exclusion later was reformed by the parties in accordance with a Texas State Board of Insurance amendment to read “the insured” rather than “an insured.” Linda Isbell and the Ryans argue that this reformed clause, in light of the severability clause, only excludes coverage for the intentional acts of the individual insured being sued. Thus, they argue, the intentional acts exclusion as reformed would be meaningless because claims arising from intentional conduct, and in particular from the intentional conduct of others, would already be excluded under the definition of occurrence.
The determination of whether an ambiguity exists in a contract is a question of law.
Canutillo,
Ill
For the foregoing reasons, we AFFIRM the district court’s judgment. 5
Notes
. The state court has abated Linda Isbell’s negligence action by joint motion and court order pending the resolution of this appeal.
. The Ryans had two Texas Standard Homeowner’s Policies with ANGIC. The first policy was effective February 28, 1994 to February 28, 1995; the second was a renewal policy effective February 28, 1995 to February 28, 1996. There are no material differences between the two policies.
. Linda Isbell and the Ryans suggested for the first time at oral argument that Charlotte Ryan’s negligence could itself be considered a separate "occurrence,” even in the absence of a severability clause. In other words, her “accident” in failing to warn the Isbells caused the injury. They have waived this argument.
See Carmon v. Lubrizol Corp.,
. Linda Isbell and the Ryans also appeal the district court’s alternative finding that the intentional acts exclusion would preclude a duty to defend in the negligence action against Charlotte Ryan. Because we find that the negligence claim against Charlotte Ryan does not allege an occurrence within the meaning given by the Policy, we do not reach this issue. We also do not address American National's argument that public policy prohibits a finding of an occurrence resulting from sexual molestation of minors for the same reason.
. We deny Linda Isbell’s motion to certify question to the Texas Supreme Court.
