User blog comment:Heinz84/Could Dr. Doofenshmirtz be Phineas and Candace's Biological Father?/@comment-2145190-20100826024810/@comment-1858894-20100826043246

I think they are becuase (I dont remember who) someone asked if there any outher last names for any of the fireside girls and SwampyM said he thought Harono (I spelled it worng..whatever) I will post the link in a bit