He is in a brain trauma rehab center. My brother lived in Mexico for over 20 yrs as he was living on SSI. He lost an arm & shoulder in an industrial accident. He was found down at home. Was flown up here to UCSD, then to the rehab ctr in Marin County, CA. The daughters had not visited him until this year. And had very little contact. The one daughter was disowned from the family after my mother died for illegal activities. (One ex: She stole my mother's credit card from her purse while my mother was crashing in ICU.) We don't want to take control. We just want to see him & see if we can find out his wishes. My sister has facetimed him & he indicated he knew who she was. We want to try to see him & find out his wishes. We both visited him in Mx about 5 years ago & he said he never wanted to leave Mx. There is a trustee of a small trust, but he could never get my brother to sign paper work for durable power of health, guardian, etc. He is not compliant & had been a criminal most of his life. But we do care about.
You and your sister have had some contact with your (criminal?) brother over the years he has lived in Mexico.
An occupational accident has caused Brother to be in US for treatment. You would like to visit him and to find out what he would like to do at this point -- return to Mexico? Something else?
His children (one of whom stole from her grandmother) haven't had contact with him while he was in Mexico. They are in contact with him now.
You want to know if his children can prevent you and your sister from visiting.
Is that about it?
Is your brother "in his right mind"? Can he speak for himself? Can he say, "I would like my sisters to be allowed to visit"? If so, I don't see that his kids have any authority to stop you.
If he is incompetent to speak on his own behalf, then the facility may be looking to the next of kin (which would be his children) for some direction.
Have you tried visiting? What happened?
I think it is quite noble for you to wish to find out what your brother wants, and presumably to help him achieve it. (?) I wish you luck. Your brother may be somewhat "stuck" as a consequence of his life choices. You may not be able to arrange things to his satisfaction. But do give it a try! Even just knowing that someone cares enough to try may bring him some comfort.
Face Time him at the nurses' station and ask him in front of staff if you can come into his room. If he says yes? You're in.
Perhaps you can contact his daughters, maybe when they're visiting him, in person, and ask them personally if you can spend a few minutes with him in their presence.
So those are a couple of ideas that could possibly change what is.
Re your thread title question, if staff is stopping you, then yes, the children can stop you by instructing staff. If you've had a restraining order put on you, then yes again. If you can get into his room without being barred? Then no, not until someone tells you that you must leave.
It's my understanding that SSI benefits will stop if a recipient is outside the United States for more than 30 days, and benefits won't start up again until the recipient is back in the country for at least 30 days.