[Karkat doesn't reply to the first bit; Kid has it spot on, so there's no need. The second on the other hand draws a short sigh.]

Shut up, you tool. Of course trolls care about their lusii. What do you think we are, unfeeling automatons who don't develop any attachment to what raised us? Sure, they can be a pain in the ass and half the relationship is learning to keep them in line as you get older, but there is something worthwhile there, even if it's different than being raised by a member of the same species.