What are my rights as a step-parent?
Requirements are almost identical to non-parents, but one provision is different for step-parents.
Under the Texas Family Code, if a person has resided with the child and the child’s parent for a period of at least six months ending not more than 90 days prior to filing the petition, and if the child’s parent is deceased at the time of the filing of the petition.
In plain English, if you have lived with a child and their parent for six months within the last 90 days, and that parent has died, you would have standing to file a lawsuit seeking custody of that child.