"If he's happy, we're happy," his children have said.

By Gillian Telling
Updated April 24, 2015 at 12:00 PM EDT
Credit: Ethan Miller/Getty Images file

Friday night’s revelation that Bruce Jenner has long identified as a woman may have been surprising to many—but apparently not to his own kids, nor to his famous step-children.

In fact, one of the first people he says he confessed his secret to was step-daughter, Kim Kardashian.

“Kim caught me one time,” he admitted to Diane Sawyer of cross-dressing, during their two-hour long taped interview.

“[Then] she kind of walked out. It was like this big secret in the family, and we never talked about it again,” Jenner says.

It wasn’t until some tabloid articles surfaced, hinting that Jenner truly was transitioning into a woman, that she asked him about it again.

“What’s going on?” Kim confronted him, according to Jenner. Jenner then told Sawyer he admitted, “All his issues, what I’m dealing with, this and that. After it was over with, I felt much better,” he says. But when he brought it up again to Kim, asking if she was okay, she said, “Well I just thought it was one of those subjects we couldn’t talk about.”

Earlier in the interview, Jenner joked that during the filming of the Keeping Up With The Kardashians reality series, he was actually the one with the most exciting tale to tell. “The one true story in the family that no one knew about was the one I was hiding,” he says. “The one thing that could make a difference in people’s lives, and I could not tell that story.”