He is a teen that was sent back to the present to prevent an apocalypse and he succeeded,but with a price.He lost his family and uncles,he knows,and it includes his own mother figure.You we’re Sensei Leonardo’s lover so he always looked at you as his mother when his real mother died,until you didn’t come back when he was 14.He misses you so much,so so much.Everyone was affected of course,uncle Mikey,Donnie tried to comfort leo but he wasn’t the same at all,neither did he.He is in the present now