'Game of Thrones' Showrunners Instructed Sophie Turner to View Joffrey as Justin Bieber

It's definitely not easy growing up on the set of a popular television show, and we imagine it's especially worse growing up on a show like Game of Thrones, which has been the most popular show out there for close to a decade now. But that's what happened with actresses Sophie Turner and Maisie Williams.

From the ages of 12 and 13, Williams and Turner have starred as sisters Arya and Sansa Stark, and have grown into women together both on-screen and off. The pair became best friends pretty much since the first time they met on set. So it's not surprising that the directors had a hard time keeping the girls in focus in the beginning.

“We’re a nightmare to work with,” Turner told Rolling Stone. “If you’re working with your best friend, you will never get any work done, ever. Anytime we tried to be serious about anything, it’s just the hardest thing in the world. I think they really regretted putting us in scenes together. It was difficult.”

But Williams and Turner were like any young girls. At the time when the world was first introduced to Sansa, the creators had to figure out a way they could best describe what they wanted Sansa to feel when she was introduced to Joffrey. They came up with telling her Sansa's reaction to Joffrey was like Sophie's real-life reaction to Justin Bieber at the time.

Turner was an admitted Belieber, as she confessed she had a, "whole wall in my bedroom dedicated to him. David and Dan always told me, ‘Look at Joffrey as if he’s Justin Bieber and imagine that life.’ That’s the trick — how to get Sophie to act!”

Now fans can see the sisters all grown up and fighting their own battles in season eight of Thrones, premiering on April 14.