This is SO magical.

When Tom Felton said he'd rewatch the 'Harry Potter' movies on IG Live, we all knew it would be cute. Now that he's actually made it halfway through the first one (he watches in installments of about 20 minutes) Tom is dropping gems at a rate that fans can barely keep up with. He has something to say about everything!

Most nuggets of insider HP knowledge are things Tom has said before in interviews, or even things fans have picked up on by themselves. This time, Tom mentioned something that nobody had noticed before - not even himself! Here's what went down.

Tom Did Another Charity Livestream

Tom Felton smiling in front of Harry Potter TV screen
via Instagram

This week Tom queued up his version of 'Harry Potter and the Philospher's Stone.' He sat down in front of his camera and let it roll.

"It's HP1, for those of you not privy, we're watching them together," he begins. "Just for s**ts and giggles."

It was actually for a more noble cause. Through #HarryPositivity, Tom uses the livestreams to drum up money for charities of his choice. This time it's the British animal welfare group 'Dogs Trust.' Aw!

This viewing sesh started with the scene when the Hogwarts students had their first flying lesson, and ended with Harry's first quidditch game. Something pretty special happened along the way.

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Tom Shares a Split-Second Moment with His Grandpa

Tom had revealed his gramps played an extra in HP1 before, but nobody knew that he and his grandpa had been so close together on film until Tom caught it for himself.

In the scene where Professor Quirrell declares there's a troll in the dungeon, both Tom AND his grandpa's reactions were recorded - then put into the movie one directly after another. The split-second cut from Tom's grandpa's face to his own face making the same confused expression caught Tom so off-guard that he had to laugh.

"That's my gramps! Oh my days, it actually goes, it goes my gramps and then me, in the same...sorry I'm really just," Tom says, struggling to find the words. He catches his breath with a sigh and then laughs out loud until onscreen Dumbledore shouts for silence.

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The Same Thing Happens in the Quidditch Scene

Old wizard and Lee Jordan Harry Potter
via Instagram

Toward the end of the livestream, Tom almost jumps out of his seat when he and his grandpa hit the screen once more.

"That's my grandpa again! The guy with the beard!" he shouts proudly. "White beard! Huge beard next to Lee Jordan! Panning in on him right now!"

What's more, the next shot is of Tom AGAIN.

"And there's me again!" he notices, shocked to see his own face right after his grandpa's. "Sorry it's just like, it's a family thing. Mental. Mental."

It's unclear whether putting the Feltons together was an intentional editing choice or a lucky coincidence, but either way - makes for a pretty adorable HP fact. Look out for them the next time you watch!

NEXT: Here's Why Harry Potter Fans Are Calling Tom Felton 'Cheap'