Kit Harington, Sophie Turner and Game of Thrones Costars Caption Hilarious 2009 Photo Together

Kara Warner

Much has changed in the 10 years since Game of Thrones went into production — especially for the youngest members of the cast, who have literally grown up onscreen and become adults in front of an audience of millions.

PEOPLE unearthed an early photo featuring a few of the youngest cast members at one of their first public outings together — a 2009 book event for Thrones author George R. R. Martin — and some of the actors were both delighted and horrified to see it.

Adam Whitehead

“I remember this day very distinctly,” Kit Harington, a.k.a. Jon Snow, told PEOPLE. “It was in Belfast and we went along to a book signing that George was having. This is the first time I ever really posed for a photo, and it was really bizarre because this is right at the beginning, none of us know what’s going to happen at this point.”

Harington’s onscreen sisters Sophie Turner (Sansa Stark), 23, and Maisie Williams (Arya Stark), 21, weren’t quite as happily nostalgic about the photo.

“Oh my God,” Turner and Williams said in unison.

“Okay, two of these five people are prepubescent,” noted Williams. “Why do five of five people look prepubescent?”

Maisie Williams, Kit Harington, Sophie Turner and Rose Leslie at the final Game of Thrones premiere in New York. | Jeff Kravitz/FilmMagic

Added Turner: “Prepubescent, that’s so true. It looks like a bunch of inbred cousins.”

“Oh God, it’s just awful,” agreed Williams. “It does like [they’re] going to their first-ever book shop.”

“Everyone just looks so weird!” said Turner.

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Harington, 32, who married Thrones costar Rose Leslie in 2018, admitted that one thing hasn’t changed from 2009 to now.

“I still pull that face in every photo shoot,” he said.

He continued: “A lot in my actual life hasn’t changed. Not my relationships with my family or parents, I hope they’re very similar to what they were. You just have this kind of bizarre job that you do. If I was to show that boy there this [photo], his mind would be blown.”

Game of Thrones season 8 premieres Sunday at 9 p.m. ET on HBO.