DNA

Voldemort has a daughter. Of course, he didn't plan on having one, since his wine was spiked with love potion. So, that means that his daughter can't love, like her father.

Who is this daughter, you say?

Her name is Taylor Arche Riddle.

She hates the fact that her father is the almighty Dark Lord that fell. She hates even sharing similar DNA as him. But, she can't change it.

"Life isn't fair," as her Uncle Severus always says.

So, since her father probably has no chance of coming back, she decides to befriend Harry Potter. But, of course, he finds a way back into her life. By sticking to the back of a person's head. She gets constant disappointment from her father because of her house and friends.

"You shouldn't befriend mudbloods,"

"You shouldn't befriend blood traitors,"

"You're supposed to hate Harry Potter, not be his friend!"

She ignores her father, deciding she doesn't care what he has to say. Even though they share the same blood, she ignores this and pretends he's not her father, or even related to her at all.

Well, you can say he isn't happy when he comes back.