So my cousin has been released out of prison 6 months ago but he hasn't acted strange till now. Just yesterday me and my sister realized something different about him as he stopped interacting with us and no longer part takes in smoking &amp; drinking. Now some of us would look at that as a good thing as sure I did but his demeanor was different and was something never seen before. He would try to force my brother to smoke by putting a cigarette close to his face and scream about how tap water is good. He showed more clear developments when his mom came over to check on him and he didn't want to eat anything nor what she bought for him, McDonalds (his favorite). His mom hugged him and he hugged her back but had an angry face on and punched the walls repeatedly beside him meanwhile hugging her. Things got even more strange when he was at his mom's house he asked his sister who she was, took his moms liquor bottle and threw the entire liquor (liquid) out over the balcony and not only that pushed his mom off her bed in the night time. Last time I saw him, really showed me that he in fact has a mental issue that developed out of nowhere as he walked out of his mom's home and walked 30mins to my house (his grandma's home) with no shirt on, coughing and pounding his chest (after effect of not eating for three days) outside laying on the grass of my home. He also yells random sayings...
As of today, he is in a hospital but Im worried about after he's done there and will return back home.
He's only 25yrs old.

I really would appreciate advice on what we should do, know what kind of disorder is this, and if he will go back to being normal because right now I feel like there is potential he can stay like this.