"After you defeat your enemies, you cannot spare their children or they will come for you once they're grown, and the cycle of revenge never ends." Yeah duh, if you're just gonna leave them there?? No shit they'll hunt you down and avenge their parents.
What you're gonna do is take them in and raise them as your own. Don't lie to them what happened, or try to hide it from them; explain why it happened. Why you really, really had to do that. Because if you can't raise someone to trust you and your judgement after killing their parents in cold blood right in front of them, then maybe you are the villain that they grew up to see you as.
Pretty sure the UN calls both of those genocide.
Why and how are you enemies with an entire ethnicity? That's pretty racist.
