Young Sheldon Season 7 Episode 3 Peeping In The Shower

Young Sheldon Season 7 Episode 3 Peeping In The Shower

see more: Russ Tamblyn’s Daughter China Recalls Meeting Him at Age 17: ‘Changed the Trajectory of My Life’ (Exclusive)

The ‘West Side Story’ star’s older daughter recalls how Russ didn’t know about her until she was a teenager, and what their relationship is like today

Russ Tamblyn is a father of two — but for the first 17 years of his older daughter China Tamblyn‘s life, he had no idea she existed.

When he did learn he had fathered a daughter with a woman named Betsy during his time focusing on fine arts in California’s Topanga Canyon, though, “I fell right into it,” he tells PEOPLE amid the recent release of his memoir, Dancing on the Edge.

“In the beginning, I was Amber Tamblyn‘s father, and then suddenly I became [a father of two],” adds the West Side Story star, 89, who explores more about the revelation in his book and shares his younger daughter, writer/actress Amber, 40, with longtime wife Bonnie Tamblyn.

China, 55, tells PEOPLE that while she “grew up hearing stories of ‘Russ the artist and gymnast,’ ” she “never knew his last name or that he was an actor.”

“When I was 13, I finally convinced my mother to tell me his full name,” she adds. “The next day, I went to the local library and looked him up. When I saw his picture, there was no doubt he was my father and I was a Tamblyn.”

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Russ Tamblyn and Wife Bonnie Reveal Daughter Amber Edited His New Memoir: She Brought a ‘Modern Perspective’ (Exclusive)

Not long after she learned about her dad, one of China’s teachers bought her a book called Where Are They Now? — and as she recalls, “In it was a photo of Russ, Bonnie and Amber.”

“I started to get more and more curious, especially with a little sister in the picture,” she tells PEOPLE. “The summer before my senior year, my drama teacher went on a trip to L.A. and brought some photos of me. He contacted Russ and, a week later, we met.”

China says that the first meeting with her dad, stepmom and half-sister “changed the trajectory of my life forever.”

“Walking into the Tamblyn living room was like being in an art gallery,” she remembers. “Not only were both Russ and Bonnie incredibly talented, I was also exposed to other wonderful artists like George Herms and Wallace Berman, and the poetry of Jack Hirschman and Michael McClure.”

China adds, “I was at the perfect age to be receptive, and I soaked it all in.”

Amber tells PEOPLE of the time before she met China, “When I was a little girl, I played with dolls and Barbies and dreamed of having a sister as cool as I thought they were.”

“I was an only child, or so I thought — or so our whole family thought,” the Sisterhood of the Traveling Pants actress continues. “When I found out I actually did have a real sister out there and I was going to meet her, it felt like a dream coming true.”

Amber remembers China, who is 14 years older, as “the coolest 17-year-old I had ever seen, with dyed green hair and the most beautiful brown eyes in our whole family. She wore a flannel, and was holding a guitar case in her hand. And she was my sister. Mine.”

The actress and author says she has always felt “so lucky to have China as my big sister — someone who has inspired me on a deep level at every stage of my life: as a mother, an artist and a wife. I look up to her in so many ways, and I always will.”

West Side Story Star Russ Tamblyn to Publish Memoir Dancing on the Edge — See the Cover! (Exclusive)

After meeting Russ, China went on to leverage the “profound effect” he and Bonnie had on her due to an “exposure to art and music. This included learning to weld, getting an art degree in sculpture and playing in an all-female rock band, having been inspired to do the latter “by my nights around the fire pit listening to Bonnie play guitar and sing.”

As for his relationship with China now, “I see her all the time,” Russ says, adding that they “bonded really, really fast” when they first met in the 1980s.

And he’s also a proud grandfather of three: to Amber and husband David Cross‘ daughter Marlow, 7, as well as China’s son Dylan, 25, and daughter Vivian, 22. The latter two have also taken up the arts and starred in a stage performance, produced by China, of West Side Story in 2013 — with Dylan as Riff, the leader of the Jets whom Russ famously played in the 1961 film adaptation.

Citing her Oscar-nominated dad’s “lucky” and “successful” life thus far, Amber tells PEOPLE, “Forget his career and look no further than the two daughters he made who grew up to be resilient, powerful women, artists and mothers, and you will know his greatest achievement of them all.”

Dancing on the Edge is available now wherever books are sold.