Hmm... Another way to get the father out of the picture is the classic: He's an adventurer or archeologist or something, and only comes home once in a while to say "Hi" before jumping into his next "years from home doingwhateverhedoes". He probaly knows about the incest, but he says "live and let live, I'm too busy now, and - Oh yeah, take care of everyone like a good boy, sorry no money, bye, bye see you and good luck".
It's not that realistic, but at least it's a funny way to get dad out of the picture without death drama...
It's not that realistic, but at least it's a funny way to get dad out of the picture without death drama...