It's not easy being besties IRL when you're playing the Stark sisters.

As Sophie Turner and Maisie Williams made their long-awaited Game of Thrones reunion in season seven's fourth episode on Sunday night, the actresses admitted that the emotional meeting between Sansa and Arya was extremely awkward to film.

To put it simply, Turner told Entertainment Weekly: "Our first scene together was our reunion scene, and we f—ked up so many times."

"We couldn't keep a straight face! Our relationship is so close, but it's only that fun side, never the business side," the flame-haired star continued during the post-episode interview. "I was nervous. It just terrified me. It's like performing for your mom. When somebody is watching, you don't do it quite as well."

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Williams also admitted that shooting the scene together was the "weirdest thing." She explained: "We were both embarrassed to do our thing in front of each other. It took a few hours for us to get serious and actually do it. Later it was fine on set and we could concentrate, but it was so hard to get into character with Sophie in front of me."

That being said, the close stars, who even share matching tattoos that recall the date of their first day shooting together, don't regret their BFF status for one minute.

In fact, they think it may even help make their acting feel more authentic. "In the long run I think it benefits us because we can be free with each other in our acting," says Turner. "We're not afraid to go there with each other because we feel so comfortable around each other."