Of all the things J.K. Rowling has gone back and added details to on Pottermore, one big question for fans remains: What happened to Lily Evans' parents in Harry Potter? I've written before about just how maddeningly little we know about Harry Potter's parents in general, especially when you consider how they were married at 18 and had Harry when they were 20. According to the books, all of Harry's grandparents were deceased by the time Voldemort attempted to kill him, which is of course why he was shuffled off to the Dursleys'. But isn't the fact that all of Lily and James' parents were dead when they were 21 years old remarkable enough to warrant some kind of explanation?
With James' parents, at least, it was a little easier to fill in some holes. He came from a prominent pureblood wizarding family that refused to join the Death Eaters, which would make them a natural target. So they were either murdered or died of old age — the narrative does mention that they are very old to be parents, which is part of why they were so indulgent with James, their only child.
But what about Lily's parents? The information we have about them is even more limited. We know that Petunia was resentful over how proud her parents were that Lily was a witch, but we have no information about their personalities, their careers, or what happened to them.
Enter Tumblr user thelittlemerms, a Ravenclaw who just offered the explanation we've been waiting for over a decade to hear. Brace yourselves, Potterheads, because the sauce is about to get rough. Here's the theory they posted to Tumblr:
SO I JUST HAD A THOUGHT
Lily’s parENTS. WTF happened to them?
Because like, okay I can assume James’s parents are dead because, you know, wizard war, but her parents are muggles. They don’t have anything to do with any of that bullshit. like what are the chances of not only Harry’s parents, but both sets of Harry’s grandparents being dead? Like, it seems like they have to be dead for Dumbledore to say that the Dursley’s are Harry’s only family but I highly doubt they died of natural causes, because at most they would have been in their fifties when Harry was a babe.
So then, did Voldemort kill them? This seems plausible, given the fact that Voldemort confronted Lily and James three times before they died and we have no idea what happened any of those times. one of those times could have involved the death of Lily’s parents.
But, I feel like James and Lily would have been smarter than that and would have done more to protect them, could this be a situation similar to Hermione’s parents, in which Lily decided to wipe their memory of her? Maybe intending to fix it one day, maybe not, but either way she died and never got the chance. And now they’re just living out their lives completely unaware of their wizard grandson.
However, given the fact that there was no indication that the Dursley’s were ever sent into hiding or felt threatened by Voldemort, I’m not even sure that this would be the case. Maybe, her parents memories weren’t erased, she just told them to move and cut off contact with them, and having already cut off contact with her sister she didn’t think she would be in danger. Likely, Voldemort probably didn’t even care that much about her muggle family members as they weren’t that much of a threat. And James and Lily didn’t bother to tell anyone where her parents were because the possibility of Harry being raised by them, raised by muggles, didn’t even occur to them. Even if they did die, they had Sirius and Lupin and Peter. No, harry would almost certainly be raised in the wizarding world.
So then, when comes time to find Harry a place to stay, Dumbledore either couldn’t find her parents or didn’t even try that hard to look, because he’s a dumbass and thought putting him with the Dursley’s was an okay plan. And Petunia doesn’t contact her parents to tell them Lily’s dead, because she’s stubborn, or because she herself doesn’t know where they are now because she hadn’t been talking to them for years before they moved anyway.
So now, Lily’s parents are just living their lives having no idea what happened to their daughter, never knowing she died, and possibly not even knowing they have a grandson.