"Game of Thrones" star Maisie Williams celebrated a special holiday on April 17. No, not Tax Day but something much better: the hit HBO show's seventh birthday.

On April 17, 2011, the now-iconic series aired its first episode. Williams was just 14 at the time and has grown up with the show, so it's not surprising that she was thrilled to mark its latest milestone. She posted a message on Twitter and included a funny nod to her character.

"A girl is well excited to celebrate the 7th birthday of ," she wrote, in part.

She also encouraged her followers and fans of the show to join her in honoring the series, and they soon delivered. Many began posting their favorite moments with the hashtag she'd directed them to use, #7Years7Kingdoms. The answers were varied, but not surprisingly, her character, Arya, got a lot of love. A girl is a badass, after all.

Meanwhile, the official "Game of Thrones" Twitter account got in the game, too, inviting fans to join in the celebration of the show's "7th Nameday."

Oh, how quickly the time has gone. At this time next year, "Game of Thrones" may very well be kicking off its eighth and final season. The show is slated to return in 2019.