Halfblood or Quarterblood?

[Seaphron]

So my girlfriend and I have been having a debate. The debate has been that Harry is not a half blood. That he should be a quarter blood.
Note: We are both aware that in the story Harry is a 'halfblood'. It was just an interesting discussion point.

Her argument is that his parents were both magical. His grandparents on his mom's side were muggle. That should make him a quarter blood. For example Snape had a witch for a mother and a muggle father with no magical powers that's half wizard half muggle. That makes him half blood. Harry's mom and dad are both magical but Lily has muggle parents which makes Harry a quarter blood. In this theory that would make Harry's kids some fraction muggle born.

My argument is that they are both half bloods because while yes Lily did have magical parents she was the first in a line of muggles. While James is from a pure blood family. My point being that it is the fact that Lily is not from a magical bloodline and this is what makes Harry a half blood.
In this theory that would make Harry's kids 3/4's blood.

Anyways gotta go for now. Just looking for opinions.

[iKarnezar]

James = 100% Wizard blood

Lily = 0% Wizard blood

Harry = 50% of each

Magical ability isn't the same as blood. A squib has 100% magical blood but 0% magical ability. A Muggleborn has 0% Magical blood and 100% magical ability.

[highclasslinda]

Half blood

[Erinnerung]

Magically speaking, Harry should be a pureblood. Culturally speaking, his mother wasn't from the wizarding aristocracy, so he's still called a half-blood.

[flight815kitsune]

Because Lily was Muggleborn, Harry's a halfblood. But I'm not sure how it works with his children. You don't really see other fractions mentioned, so I think all the Potter babies would now be purebloods?