Legal Question in Family Law in Texas

Forget it. The cell phone company will never comply with the subpoena. Send her requests for production asking for her cell phone records including on-line records. When she fails to give them to you (which she will) ask the court to order her to give you a release to obtain the records yourself.

But if the issue you are trying to uncover is infidelity, why? It won't have anything to do with child custody and will have little or nothing to do with the division of the marital estate. You may be about to work yourself into a froth for no good purpose.