How can my 92 year old Mother take her house back and force my brother out of her house?

. It has recently come to light that my Mother unknowingly signed over half of her home to my younger brother as a “Co-Tenant” on her house. When I explained this to her she said that she had no idea that she had done that and did not ever want it that way. My Mother has demanded that my brother “Give Back” her house but he now refuses to do so. My Mother is 92 years old. My brother has lived off my Mother for the last 30 years. He lives with my Mother but has not worked at any job, my Mother pays all the bills including food. He has never paid rent, anything toward taxes, insurance or upkeep toward the house. My Mother is fed up and wants him out. Is there any legal way for my Mother to take her house back and force my brother out?