John Stamos is opening up about being sexually abused as an adolescent by a babysitter.

The “Full House” star says the memories of the alleged abuse were “always in the back” of his mind, but it took writing his upcoming memoir, “If You Would Have Told Me,” for him to realize he was abused, People reports.

Stamos, who has been a celebrity ambassador for ChildHelp, a nonprofit dedicated to the prevention and treatment of child abuse, for more than 20 years, says he “packed it away” like many victims have.

“I do so much advocacy for the [survivors]. I felt like I remembered it slightly,” Stamos, 60, told People Wednesday. “It has always been there, but I packed it away as people do, right?”

The actor said he “didn’t tell” anyone about it because, at the time, he didn’t understand the gravity of the situation.

“I think I told myself, like, ‘Ah, it’s girls, man,’” Stamos explained to the outlet. “It was like you’re playing dead so they’ll stop. But it wasn’t totally aggressive. I don’t know, it was not good.”

He added: “I was probably like 10 or 11 [at the time]. I shouldn’t have had to deal with those feelings.”

The former soap star reportedly attributed becoming a parent and the death of his friend and “Full House” co-star Bob Saget for pushing him to finally tell his story, Deadline reports.

The “You” actor shares a 5-year-old son with his wife, Caitlin McHugh Stamos, whom he married in 2018.

“Honestly, while writing this book I’ve realized I have about a million stories to tell, and I think you may like at least four hundred of them. It has been cathartic and healing and sometimes heartbreaking to dig in and reveal so much,” Stamos said in a statement last year.

Representatives for Stamos did not immediately respond to HuffPost’s request for comment.

Speaking to People, Stamos said recounting the alleged abuse only spans “a page or something” in his memoir because he “didn’t want the book to be” about that.

He admitted he was hesitant to recall the incident within its pages because he didn’t want that to become the main focus of the book.

“I didn’t want the headlines to be that, and I didn’t want the book to be over that,” he explained. “It was a page or something, but I felt I had to talk about it. It was weird.”

Stamos added: “But I’ll tell you, if I found out someone was doing that to my son? That’s a totally different story.”

“If You Would Have Told Me” is set to release on Oct. 24.

Need help? Visit RAINN’s National Sexual Assault Online Hotline or the National Sexual Violence Resource Center’s website.