Texas Family Code - FAM § 102.004. Standing for Certain Relatives and Other Persons

(a) In addition to the general standing to file suit provided by Section 102.003, a grandparent, or another relative of the child related within the fourth degree by consanguinity, may file an original suit requesting managing conservatorship if there is satisfactory proof to the court that:

(b) An original suit requesting possessory conservatorship may not be filed by a grandparent or other relative or person.  However, a grandparent or other relative or person may intervene in a pending suit under Subsection (b-1) or (b-2), as applicable.

(b-1) A grandparent or other relative of the child within the fourth degree of consanguinity may intervene in a pending suit filed by a person authorized to do so under this chapter if there is satisfactory proof to the court that appointment of a parent as a sole managing conservator or both parents as joint managing conservators would significantly impair the child's physical health or emotional development.

(b-2) The court may grant a person, other than a grandparent or other relative of the child within the fourth degree of consanguinity, subject to the requirements of Subsection (b-3) if applicable, deemed by the court to have had substantial past contact with the child leave to intervene in a pending suit filed by a person authorized to do so under this chapter if there is satisfactory proof to the court that appointment of a parent as a sole managing conservator or both parents as joint managing conservators would significantly impair the child's physical health or emotional development.  The court may not grant a person leave to intervene under this subsection unless each parent consents to the intervention.

(b-3)  A foster parent, relative, or designated caregiver may only be granted leave to intervene under Subsection (b-2) if the foster parent, relative, or designated caregiver would have standing to file an original suit as provided by Section 102.003(a)(11).

(c) Possession of or access to a child by a grandparent is governed by the standards established by Chapter 153.