I wish I knew if he was legitimately mentally handicapped... I’m pretty well convinced he’s somewhere on the spectrum and should probably wear a soft helmet, 7-on-7 style, anytime he leaves his house - so I, by and large, give him a pass...
but assuming he has no serious physical conditions, everyone in his life has done him - and the world at large - a great disservice by not beating the absolute dogshit out of him years ago, and continuing to do so until he got the message
it’s also not too late... I believe anyone can still be salvaged, regardless of age or how far gone they appear to be, with a properly administered strong, christian asswhuppin