It does indeed and there's nothing like a shared punishment to make kids become closer, or at least less antagonistic.  It was what Severus hoped would happen between thse two, since the both of them are so alone, and yet they both have similar kinds of abusive pasts to live down.  Many people tend to think that just because you come from a well-to-do home vs a poor one, that nothing abusive goes on there.  Well, that's wrong, since background is no bar to abuse, but a child of rich parents might be able to hide it longer. 

Harry is finally able to see that and now they can start to bond together as siblings.  And I'm the youngest of 5, so all my sisters and my brother protected me.  And my cousins, who lived right behind the elementary school I went to.  Once, some other kids were picking on me, beating me up or whatever, and my siblings had moved up into a different school, but a few of my cousins were still around and we had this whistle code, if one of us was in trouble, we would whistle a certain way and whoever was nearest would come and beat up the kid who was hurting our family member.  Well, I did that whistle, and three of my cousins, they were girls but they knew karate and stuff, came and they nailed the older kids that were bothering me so bad those bullies never came near me the whole five years I was in that school.  I think they told the other bullies to leave me alone, because I never had any more problems after that.  having siblings is wonderful, sure you fight with them occasionally, but they are also there to rely on when you need something or want to talk or whatever.  I don't know what I'd do without mine.  Those poor kids without sisters or brothers--man you've gotta feel sorry for them!