When I was a little kid (80ies) I saw a two part tv miniseries in italian language in the italian tv. It does not have to be Italian, nor a miniseries. but I remember it that way.
This is how I remember the story: Two orphaned siblings (their parents just died) are sent into an orphanage. There they met another boy, a bit older than them. The conditions in the orphanage are bad and the older boy is escaping the facility (not for the first time) and the little two kids are secretly following him. the smaller kids have no idea how to survive on the street and the older boy feels responsible for them. he teaches them how to survive as street kids and together they make an earning by stealing/pickpocketing. As time goes by they decide they cannot live like this forever and they want to be in a more stable environment. The older boy suggests that he will start working and earn money for all three of them. He starts in a restaurant and washes the dirty dishes. His boss is a mean and cruel man and after an argument he tosses the boy to a wall and has the boys head severly injured. The boy now has brain damage and is hospitalized. He will never recover because of the brain damage. The two little kids visit him in the hospital and when they see the boy they can’t bear seeing him like that. Not able to speak and drooling. They take a pillow and suffocate him to release him from pain and a life not worth living.