Michelle has it. When I was a kid I had a female classmate whose little brother was an absolute nightmare to be around. The one time I went over to her house to play her mother insisted that he, 2 or 3 years younger, be allowed to play with us, but as you would expect in that situation he was kind of left out because younger and still nonverbal at an age where most kids are talking (no diagnosis of any kind, because the 70s). The girl and I were having a conversation and he didn't like the fact that we weren't paying much attention to him, so he bit the inside of my upper arm, really hard. At which point I of course got pissed off and went over to show my mum, who was also pissed off, but the weird part was that the boy's mother acted like her child biting people was just something everyone else should ignore or work around. Apparently he bit his sister all the time, and his mother's explanation of this was oh well, he doesn't usually break skin so (shrugs). The sister was expected to just put up with this, and with the fact that every time she made a new friend they ended up not wanting to come over any more because the brother was allowed to bite and hit and kick and the parents would just stand there watching him do it and scold the other children about not being understanding enough if they complained. This wasn't a toddler btw, he was maybe about 5? So not only did his sister get bitten and smacked and kicked all the time, she ended up with no friends except at school, because her parents wouldn't let her go play at their houses instead since they viewed it as her job to entertain her little brother and keep him busy. And this completely dysfunctional dynamic continued for as long as we knew them.The parents were outraged by the very idea of the school trying to control the boy's behavior, they expected them to just put up with it too and allow the other children to be hurt, and any attempt to point out that this really wasn't fair to everyone else was met with demands to be kinder and more understanding and well he can't help it so obviously the other kids should just accept that and not try to avoid him because he kept hurting them. It only took one incident for my mum to decide I wouldn't be going over there anymore, but his father worked with mine so we were in touch with this family off and on until both kids were in their mid twenties and they seem to have maintained the same everyone else is the problem attitude the whole time.
I mean, it was great that my mum backed me up and said nope, not letting my child be bitten and no I'm not letting her be guilt tripped into putting up with it because that's what would be "nice" and "considerate", but what about his sister? And the poor kids in his class, and his teachers who had to deal with a totally out of control child whose parents thought that his behavior was just one of those trials one must live with and it was the fact that other kids didn't want to just put up with it that was the problem?
Whenever anyone starts banging on about teaching children that they must be kind to everyone regardless of whether the other person is kind back or that they have a moral obligation to include all their classmates in their games and other activities I think of that little boy and his poor bruised and bitten sister whose childhood was spent being lectured about how she should learn to be more understanding towards the brother who kept hurting her.