WATCH: How Yuh-Jung Youn's memories of her own great-grandmother inspired her 'Minari' role

When Yuh-Jung Youn appears in the film "Minari," playing grandmother Soonja, her young grandson isn't warm to her arrival. David, who has to share a room with her, tells her early on, "you're not a real grandma."

David, played by Alan Kim, rattles off how other grandmas are unlike Soonja: "They bake cookies! They don't swear! They don't wear men's underwear!" Soonja, unphased, playfully kicks at David. That initial tension, however, starts to dissolve as Soonja forms a bond with her grandson. A throughline of "Minari" is Soonja's love — like any grandmother's love — for her family, even if it's not always understood.

The film, written and directed by Lee Isaac Chung, follows the Yi family as they move to Arkansas' Ozark Mountains in the 1980s. Youn, whose career has spanned more than five decades, said she drew from her own experiences as a grandmother for the film, but also built the character of Soonja by relying on memories of her own great-grandmother, who was alive until Youn was 10 years old.

Youn said she and Chung, the director, were both bad to their grandmothers when they were younger.

After the war, there wasn't enough water for each family, Youn said. "[My great-grandmother] tried to save the water. Then I found she was just washing [with] the dirty water. Felt like she was so dirty. Not hygienic. So that's why I don't like her. Isn't that stupid?"

Youn also recounted how her great-grandmother, amid a food shortage, would also say she wasn't hungry and would skip meals to help preserve more food for the family.

"I didn't know at the time," Youn said, tearing up. "That really hurt me. Still. While I'm talking about my great-grandmother, every time, it's not acting."