SESKA: Hello, everyone. What do you think of your son, Chakotay? He has your eyes, don't you think? Thank goodness he doesn't look too human. You all have such weak foreheads.
CHAKOTAY: May he grow up never knowing the contempt his father has for his mother.
CULLUH: I think I can assure you of that, Commander. I intend to take him for my own son.
So there is that. Perhaps Kazon society has a tradition of taking on male children as a part of your "house".