Before Caitlyn Jenner transitioned in 2015, she spent decades hiding her true self - and kept secret her penchant for dressing up in women's clothes.
Relegating a small collection of dresses and feminine outfits to the back of her locked closet during her marriage to Kris, Jenner went to great lengths to shield their kids and only dressed in women's clothing when she was at home alone.
Her precautions worked well - until one night, that is.
"With everyone out of the house I dressed up," Jenner writes in her new memoir, The Secrets of My Life, excerpted exclusively in this week's PEOPLE.
"I went into Kylie's room to check myself out because it had a full-length mirror."
Little did she know, however, the girls' computer camera was on - an effort for one sister to catch the other in the act of stealing wardrobe - and it inadvertently recorded Caitlyn's dress-up session.
"Later that night I heard them running to their mother yelling, 'Oh my God, what's on the computer screen?!'" says Jenner.
"They were mercifully too young to understand."
It would be years before Jenner told her kids the full extent of her lifetime of turmoil and plans to publicly transition.
For the exclusive excerpt of The Secrets of My Life and an interview with Caitlyn Jenner, please pick up this week's issue, on stands Friday.
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