Not the child, but the parents.
One child from my DD's school comes to our house regularly (9yrs old)and to be honest he stinks of cigarettes 
It is so bad, that if he is in a room, it takes ages to get rid of the smell.
He is at school all day as well, surely the school must notice. Do they ever approach heavy smoking parents about their children's cleanliness?
Just feel so sorry for the child as other kids are teasing him about it 