Kieran Culkin Reflects on Sister Dakota's Death 16 Years Later

Kieran Culkin lost a "big piece of himself" when his older sister, Dakota Culkin, died in 2008.

The Succession actor, 42, grew up in a large family with six siblings, including Macaulay Culkin and Dakota.

Dakota worked on the opposite side of the camera as an art production assistant on the 2009 supernatural thriller Lost Soul. Dakota was 29 when she was struck by a car while crossing the street in Marina del Ray, Calif., in 2008.

"I only knew who I was because of who my siblings are," Culkin told CBS Sunday Morning in an interview published on Sunday, Nov. 3. "So, to lose one was losing a big piece of myself."

Culkin says the pain of Dakota's death is something he's had to learn to live with.

"Losing one of my favorite people in the world, it doesn't get better," he continued. "It doesn't get easier, but you get used to it."

Culkin found a way to keep his sister's memory close to him in the years following her death. He said his Succession character Roman Roy's humor reminded him of his sister's humor.

"After a couple seasons, I realized there was some stuff that Roman did that I was like, 'Oh, that's my sister,' " he explained. "'That was her sense of humor.' She could find exactly what the right thing to make fun of you was that would get to you, but be really funny and make the room laugh. That was her."

The siblings were extremely close growing up, Culkin said. They stuck together and Culkin took on a protective brother role, always making sure everyone was accounted for.

"Whenever the door would open to let the kids in," he shared. "I used to stand aside and count to make sure all six of them got in before I got in. That's how I remember growing up, too. I couldn't fall asleep until they all fell asleep. I only existed because they did around me."

Dakota was the second child of Kit Culkin and Patricia Brentrup. At the time of her death in 2008, Dakota had recently moved from New York City to Los Angeles to pursue a career in film production, her friend Andrea Poe told PEOPLE .

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"She was very low-key [about her name], but at the same time proud of her siblings," Poe said. "She was very close to Macaulay. They would talk frequently on the phone or go out to eat."

Dakota's name lives on in the Culkin family line. When Macaulay, 44, and Brenda Song, welcomed their first child in 2021, they named the baby boy Dakota .

Culkin, who has two children — Kinsey and Wilder — with Jazz Charton , 36, said it's difficult knowing that their children will never meet their aunt.