S.C. Code Ann. § 20-7-1540 – De facto custodian of minor child; visitation; custody

(A) For purposes of this section, "de facto custodian" means, unless the context requires otherwise, a person who has been shown by clear and convincing evidence to have been the primary caregiver for and financial supporter of a child who:
1. (1) has resided with the person for a period of six months or more if the child is under three years of age; or
2. (2) has resided with the person for a period of one year or more if the child is three years of age or older.
  Any period of time after a legal proceeding has been commenced by a parent seeking to regain custody of the child must not be included in determining whether the child has resided with the person for the required minimum period.
(B) A person is not a de facto custodian of a child until the court determines by clear and convincing evidence that the person meets the definition of de facto custodian with respect to that child. If the court determines a person is a de facto custodian of a child, that person has standing to seek visitation or custody of that child.
(C) The family court may grant visitation or custody of a child to the de facto custodian if it finds by clear and convincing evidence that the child's natural parents are unfit or that other compelling circumstances exist.
(D) No proceeding to establish whether a person is a de facto custodian may be brought concerning a child in the custody of the Department of Social Services.
(E) If the court has determined by clear and convincing evidence that a person is a de facto custodian, the court must join that person in the action as a party needed for just adjudication under the South Carolina Rules of Civil Procedure.