Stumbled on this and, although I've never been a big Donald Duck fan, I have to admit I spent some time perusing it.
First off, this is a family with anger issues.
Secondly, I never knew we didn't know who Huey, Dewey and Louie's father was:
Her husband is a mystery, as he is hidden by a bird on Rosa's family tree and part of its branches. The only thing apparent: his last name is "Duck". It has been found out that he went to hospital because Huey, Dewey and Louie have put a firecracker under his armchair as a prank, but the result was quite harmful. It was because of this incident that Dumbella sent her sons to her brother, Donald Duck. it was supposed to be for four weeks, but she never brought them back… Apparently, they couldn't cope with their kids anymore and left them indefinitely with Donald.
Thirdly, Dirty Dingus McDuck looks especially scary. And his name sounds like a medical condition.