If all you have done is place your home on his property, your home is not in jeopardy.
But, if your brother is foreclosed upon, the bank will ask you to move your home.
If you don't, the bank will request a court order you to move your home.
However, the bank may not ask.
The bank may go directly to the court and ask for a court order to force you to move your home.
If I were you, I wouldn't wait for that to occur.
I'd make my own arrangements to relocate ASAP.