Tennessee Code Title 36. Domestic Relations § 36-6-117

(a) In determining a custody arrangement under this chapter that is in the best interest of the child, the court shall not consider it a negative factor for a parent to raise, guide, or instruct or intend to raise, guide, or instruct a child consistent with the child's biological sex, including, but not limited to, referring to a child by titles or pronouns consistent with the child's biological sex or making mental health or medical decisions based on the child's biological sex, including, but not limited to, consenting to any lawful medical or mental health service to assist the child in living consistent with the child's biological sex and declining any medical or mental health service for the purpose of gender transition.

(b) This section does not limit the court from considering any other factor relevant to determining what custody arrangement is in the best interest of the child, as provided for by law.