Family

So kinda a odd thing to ask but I had an uncle in a psyc ward for most of my life tell 09, from my moms side. He’s the only family member I knew of hers. I wanna look into this all because my mother is so full of secrets about her life and past and family. I’m curious if I’d be able to ask the psychotic hospital for his records as he’s passed? Or where I could start looking into this. I have been debating a privet investigator but that can get quite costly.. and I’ve done a little bit of a google search but I’m really unsure of names other then my uncles