How are they related?

Hey guys! long story, short. I was watching 'Malcolm in the Middle' and I was wondering how any of them are related to any of the parents, because i noticed they all have blue eyes i think, and the parents have brown, plus stewie has blond hair and the parents have brown, lol how is this possible?

You don't need to get them directly from ya parents :/

I'm actually shocked at this thread. :P

lol, just felt like posting it, dunno why lol.