@wallsg
I completely agree that you can only do what you know how to do. However this isn't exactly one of those cases. The mom clearly has some personal traumas/regrets about something, and she is taking it out on her kids in order to push them to be better. And in a physically violent manner as well.
I think the difference between yours and her situations is that these are 2 very different kinds of behavior. The FMC's mom, as well as the brothers seem to know that what their mom is doing to them is considered abusive. She herself even seems to realize it a bit too. MC even tries to hide the fact that he is being abused.
As opposed to invisible trauma, which tends to be very hard to notice at first or while it is happening, since there are sometimes no easy identifiers, as per say a cut or bruise is for physical abuse.
The fact is that their mom is abusive, and she may even know that herself, but isn't doing anything to correct herself until just recently when it was blatantly told to her face by someone outside of their family.