For those who don't care, please don't read this if you don't want a fan-war.
And yes, I know that Dan and Swampy wouldn't care about such subjects either, but I don't care and I want to deliver my thoughts.

Hello, there! Someone had made a suggestion on my previous blog post that I should post my opinions about including theories about Heinz Doofenshmirtz, Roger Doofenshmirtz, and Norm being Phineas and Candace's biological father. I find it hard because I don't believe that either of them are Phineas and Candace's biological father. So, I'll make a blog on why I think it's impossible for them to be Phineas and Candace's biological father.

Doofenshmirtz family

In general, I don't even think that Phineas and Candace are related to the Doofenshmirtz family. Why?

Doofenshmirtz family reunion
The Doofenshmirtz Family Reunion.

It's the Doofenshmirtz Family Reunion seen in "Thaddeus and Thor". In the following picture, I can't see any member of the Doofenshmirtz family with a nose like Phineas, or anyone who looks like Candace, of course. Dan Povenmire and Jeff "Swampy" Marsh must've payed attention to the genetics, since Dr. Doofenshmirtz does distinctively look different from Phineas aside from the triangle heads. Phineas has no chin, while Dr. Doofenshmirtz has a quite large chin.

Heinz Doofenshmirtz

Meatloaf Surprise Image32

The popular candidate for Phineas and Candace's real father.

The first ever character I believed to be Phineas and Candace's biological father is Dr. Doofenshmirtz. I thought that, because Heinz has a similar triangle-shaped head and build amazing things, they might be related by blood. I soon found out that fans also believed that this is true. Even in the supposedly evidence that this is false, "What Do It Do?", I still believe that Heinz is Phineas's biological father. It was until I watched "Thaddeus and Thor" when I started to not believe the theory.

So, apparently, Heinz Doofenshmirtz isn't Phineas and Candace's biological father because first, "What Do It Do?". In the episode, Dr. Doofenshmirtz stated that he had a date with Linda Flynn before. It didn't went well, and Dr. Doofenshmirtz said that he never met her again.

The the final move? Well, Dan Povenmire said in the interview that Dr. Doofenshmirtz isn't Phineas and Candace's biological father, and the Linda and Heinz blind date from "What Do It Do?"'s purpose is to "fuel the fire" that Dr. Heinz Doofenshmirtz isn't Phineas's biological father.

Roger Doofenshmirtz

While a number of fans don't believe that Heinz Doofenshmirtz is Phineas and Candace's biological father due to many reasons from the complicated implications (such as if Dr. D is Phineas and Candace's real father, than Vanessa would be their half-sister and the time with Charlene Doofenshmirtz and such) to "What Do It Do?" to Dan's respond, a number of a number of those fans believe that Phineas and Candace must be related to the Doofenshmirtz family somehow.

So... why not Roger Doofenshmirtz, Heinz Doofenshmirtz's younger brother and the proud mayor of Danville himself? He's related to Dr. Doofenshmirtz, and he must have the same "triangle head", "lactose intolerance", and "creating amazing things" genes.

To me, I don't believe that Roger is Phineas and Candace's biological father because there's not much proof. Not only that, the reasons are mostly the same as why I don't think Phineas and Candace are related with the Doofenshmirtz family by blood at all.