As for Kalibak, it's the classic case of favoritism. Darkseid saves all of his, well I wouldn't call it love, but interest for his other son Orion. And, actually, Darkseid is just so generally evil that on a relative scale even Kalibak is a golden boy. When Darkseid kills Kalibak for displeasing him, for instance, he always brings him back to life. What an old softie.
Butters is the saddest one for me because it's just too realistic. His dad and his mom really are just wrapped up in their own stuff and don't care about him, to the point where his mom tries to kill him as part of their selfish relationship drama and then they both try to cover it up. They also physically abuse him. What Peter Griffin does to Meg is like a Bugs Bunny cartoon, what happens to Butters happens all the time.