If the father already opened a custody case in California, can another be opened in Texas?

If she has, he needs to file a plea to the jurisdiction in Texas.

If there is an open dissolution case in California, and it has been served on the wife, then jurisdiction should remain in California. There are also Automatic Temporary Restraining Orders in California that prevent such a move without consent. Should she file her own case in Texas, your brother would need to hire an attorney there to contest jurisdiction, as California has jurisdiction over the dissolution, including the child. In California, he should seek out an attorney and go in on an ex parte basis for an order to bring the child back to his home state of California.

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