The actress was cast in the role of the youngest Stark sister on Game of Thrones in 2011, when she was just 14, and played the role until she was 22.
But, according to Williams, there were times when dressing as Arya made her feel “ashamed” of her own body - especially as she started to “mature”.
Speaking to Vogue, Williams said: “Around season two or three, my body started to mature and I started to become a woman but Arya was still very much like trying to be disguised as a boy.
“I had really short hair and they’d constantly cover me in dirt and shade my nose so it looked really broad and I looked really manly.
“They’d also put this strap across my chest to flatten any growth that had started and, I don’t know, that just felt horrible for six months of the year, and I felt kind of ashamed for a while.”
Since Game of Thrones ended, Williams said she has experimented with a new phase of style that makes her feel more feminine, adding that it has been “nice” to embrace her body.
“In this new phase of my style it’s nice to look more feminine, have a real waistline, and, you know, embrace the body I have,” she said.
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