My biggest question is why would the father do all of that?

I get that his child looks exactly like her mom,but the mom sacrified her life for the brother so it's not her fault or maybe she was the one who wanted to go out but like,is that really enough reason for you to make your own child suffer.Plus if your mature you know that it is not the childs fault.So the ML did all that for succession.I mean he could show kindness a little bit it's not like the father watches his every move like a cctv,like showing kindess to a stranger.