When my sister lived in California she had to sign a paper giving up her right to gun ownership.

I have a legal question. When my sister was giving birth to her daughter she had severe complications with her pregnancy and almost died giving birth. She was in a lot pain while giving birth and started yelling stuff like "Oh my god I wish I was dead, kill me." She and her baby almost died due to her doctors incompetence. Her husband who is in the army was really pissed at the doctor and yelled at him and said he was going to sue and all sorts of stuff. The doctor after she gave birth then had her institutionalized for a few days claiming it was California state law that any patient threatning to kill themselves had to be reported and institutionalized until a psychological screening. My sister was told the state could take her baby and they could keep her for weeks unless she signed a paper admitting she was suicidal and giving up her right to own a gun for ten years. My sister's husband has now been transfered to Texas, he is enlisted and the base housing he was assigned to is next to the ghetto and is not guarded, you don't have to have a military ID to enter the housing area, there is no gate. He has said he has gotten word that he will be deployed within the year overseas. I suggested my sister buy a gun to protect herself and her baby while he was gone and thats when she told me what happened after she gave birth in California, I was not there. Is this restriction enforcable or applicable outside of California? I told her it was bullshit and she should have sued and it wouldn't be enforcable in Texas, was I wrong?