I mean, why MC father is so mad that the MC beat his siblings? It's not like he's not his son, just don't make any sense, if it was MC uncle i would get it, but it's his own father that didn't wanted to consider the MC his own son because he wasn't powerful, and now that he's powerful he throw a tantrum like a kid, seens like the author just did that to give MC the opportunity to get more powerful whenever he wants with the excuse "his father did that to kill/humiliate him"