I'd only pursue involuntarily taking away your sons' self-guardianship rights if there was trouble surrounding legal contracts. The problem isn't legal contracts. The problem is bed availability. Getting guardianship over him isn't going to magically make a bed available in a psych hospital. You might[/i] be involuntarily commit him if he starts showing suicidal tendencies or you might not. It probably won't matter, anyway. He'll probably get released in the same amount of time.
Guardianship can also take away rights that you don't anticipate--where I live, if an adult isn't their own guardian, they can't vote, drive, or marry [i]at all, even if they would otherwise be able to do so.
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Living with one neurodevelopmental disability which has earned me a few diagnosis'