Maisie Williams and Sophie Turner make fun of Sean Bean's clapper board skills

Even Sean Bean can't do everything. Photo / Supplied

He may be their revered on-screen dad, but even much-loved patriarchs aren't safe from a little good-natured ribbing from their fake daughters.

Sitting down with news.com.au earlier this year, Sophie Turner and Maisie Williams reminisced on their early days on Game of Thrones, which is available this week on DVD and Blu-ray.

Williams, 22, and Turner, 23, were only 13 and 14 years old when they first started on the global TV phenomenon. They're great friends, frequently goofing around together on press tours and making cameo appearances on each other's social media profiles.

Even though their characters, sisters Arya and Sansa Stark, didn't get on at the beginning of the series, it's clear Williams and Turner took an immediate liking to each other.

Thinking back to their first day on set in season one, Williams said: "I remember they put us on the opposite ends of that feast table, and I was thinking, 'now I can't chat to Sophie all day!'"

"I know!" Turner chimed in.

"That was a fun day," Williams added. "We got to do clapper boards that day."

"Oh! We did!" Turner said.

Maisie Williams (L) and Sophie Turner have been firm friends since they were first cast as sisters in Game of Thrones, aged just 13 and 14 respectively. Photo / Getty Images

Clapper boards, if you're unaware, are the black boards that production assistants place in front of the camera and clap together to mark the start of a scene. It has on it information about what they were shooting, the scene, the take and more.

It helps editors assemble the footage later on. Not using clapper boards can be disastrous to a production, as Sydney Pollack found out when he filmed an Aretha Franklin performance.

It may seem like an easy task, the clapper board, but not everyone is great at it, Williams and Turner revealed.

"And then Sean (Bean) did the clapper board and he wasn't very good at it," Williams said. "How many times has that man had a clapper board done in front of him? I was like, 'Come on, you've got to do better than that!'"

Turner added: "Sean, come on!"

Maisie Williams as Arya Stark (L) and Sophie Turner as Sansa Stark in Game of Thrones. Photos / Supplied

Bean, 60, played Ned Stark in Game of Thrones and his death in the penultimate episode of the first season was the moment fans knew this series meant business. If your lead character is disposable, then no one is safe.

Game of Thrones wrapped up earlier this season after eight wildly popular seasons, even if the final episodes proved to be controversial among the fandom.

The show's worldwide reach made stars out of many of its younger and then-inexperienced cast, including Williams and Turner.

Turner has gone to star as Jean Grey in the X-Men movie franchise while Williams' forthcoming X-Men movie The New Mutants is due for release in 2020.

• Game of Thrones season eight and complete collection is available now to buy on DVD and Blu-ray.