How does Texas handle child custody when parents live in different cities?

Yes, a material and substantial change in circumstances — like a 500-mile relocation — is grounds to modify a custody order under Texas Family Code §156.101. Courts will look at the best interest of the child, considering the impact on the existing schedule, each parent's ability to facilitate a relationship with the other parent, and the child's preference if they are 12 or older. You should file a Petition to Modify the Parent-Child Relationship in the court that issued the original order. Consider mediation first to avoid a costly trial.