Legal Question in Family Law in Texas

I'm not sure if this is necessarily the best answer to the problem, but depending on exactly what's going on, contacting the police is one available option. If the grandmother honestly feels justified in not returning the child for some reason (allegations of abuse, for example), obviously filing a police report could be opening up a whole new can of worms. Also family members tend not to be too friendly after you've called the cops on them, so there goes Christmas at Grandma's house. But if this really is just some instance of the grandmother having irrationally decided not to return the child to the parents, and an unsuccessful attempt has already been made to talk things out, there may not be much other choice.

There is one potential caveat to that, though--if the parents have voluntarily had the child living with the grandmother for at least six months, that does give her certain legal rights that she wouldnt otherwise have, and she may be able to go to the family court and ask for custody of the child.