Mark Ruffalo Shares Rare Photo of His Two 'Long Haired' Kids, Jokes 'If Only I Knew Who Was Who'

Mark Ruffalo is working on telling his older kids apart as they're currently rocking the same hairstyle.

On Monday, the 13 Going on 30 star, 54, shared a rare photo to Instagram of two of his kids, daughter Bella, 16, and son Keen, 20, showing off their similar hairdos.

In the shot, Bella and Keen sit next to one another with their heads down to reveal their nearly identical haircuts. Ruffalo shares Bella and Keen, plus daughter Odette, 14, with wife Sunrise Coigney.

"Good morning to my beautiful long haired kids… if only I knew who was who," Ruffalo teases.

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The Avengers star seldom posts shots of his family on social media, last sharing a picture of Bella to Instagram over the summer.

In the photo, Bella sits in the car's passenger seat while looking into the distance. Her curly hair is tucked into a striped gray beanie, which she paired with a navy sweatshirt and star-printed face mask.

"My daughter, Bella, so big and beautiful and coming into her own," Ruffalo captioned the snap.

Ruffalo has been married to his French actress wife since 2000.

In a November 2019 interview with PEOPLE, Ruffalo admitted that balancing his career with life as a father of three isn't always easy.

"It's intense," the Spotlight star said at the time. "The times when my wife is gone and I've had to take care of everything … the laundry alone is enough to destroy you."

He also praised his wife for shouldering more of the responsibilities at home, calling her "just a hero."