Dís is supposed to be stern in a way that makes people be a bit scared of her. I would like to suggest Glenn Close for this role, I think she'd be great. https://www.imdb.com/name/nm0000335/
Michelle Fairley, Actress: Game of Thrones. Michelle was born in July 1965, the second child of publican Brian and nurse Theresa Fairley. As a teenager she attended the Ulster Youth Theatre before moving to Belfast , where she was a member of Fringe Benefit, a repertory company where she acted...
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Age: 55
Height: 5'5"
Roles: Catelyn Stark in Game of Thrones, Margot Al-Harazi in 24: Live Another Day, Margaret Beaufort in The White Princess, Cassius in Bridge Theater's Julius Caesar
She can play both positive and negative maternal figures.