Brie Larson Drew On Her Childhood Growing Up With a Single Mother for Inspiration in 'Room'

— -- Brie Larson says her portrayal of a young mother held captive with her son in "Room" was something that had echoes of her own childhood.

As a young girl, Larson moved to Los Angeles, where she shared a cramped studio apartment with her sister and their newly single mother.

"We lived in just a studio apartment with just a room and a bed that came out of the wall, and my mom couldn't afford even a Happy Meal. We ate Top Ramen," Larson recalled in an interview for the ABC News special, "Journey to the Oscars" hosted by ABC News' Robin Roberts. "I had no toys, and I had like two shirts, a pair of jeans and that was it. But I had my Mom to myself and I remember it being the coolest period of time. I loved it. I really loved it."

"For me, 'Room' is an opportunity to relive an aspect of my childhood that I hadn't put a ton of thought into," said Larson.

Larson said "Room" also echoes her life now.

"It's such a powerful metaphor for me now, and it trips me out that this movie is the thing that's given me that experience," Larson said.

"It's saying goodbye to the 7-year-old that was in the studio apartment that was blissfully unaware and also so hopeful of what was going to happen [and] saying goodbye to my old normal," said Larson.

"Ma has to commit to living in a bigger, more complicated world, and that's what I have to do as well."

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