User blog comment:Heinz84/Could Dr. Doofenshmirtz be Phineas and Candace's Biological Father?/@comment-2145190-20100826014540

Okay, a lot of people say it's not possible because for that to happen, Heinz would have had to have a complicated relationship with Char and Linda.

But what about this (this is probably not appropriate for children under 13): What if Linda never had a marriage before Lawrence? And one day, Doof donated to a sperm bank, and Linda decided she wanted a baby, so she went to the same bank, and happened to pick out Heinz's sperm, and became pregnant with it, and that was how she came to bore Candace. And about 6 or 7 years later, the same event happened and Linda became pregnant with Phineas? How does that sound?