Angelina Jolie managed to keep her double mastectomy a secret from February 2, when procedures started, through April 27, when they were completed, and all the way until May 14, when she revealed everything. But some stars have kept their secrets even longer: Radar lists 18 of them.
- Janet Jackson put a rest to rumors last year that she was engaged to Wissam Al Mana ... by revealing that they were already married.
- Liv Tyler was born Liv Rundgren and always thought Todd Rundgren was her biological father—but it was actually another rocker, Steven Tyler.
- Jack Nicholson found out—after his grandparents and mother died—that the woman he thought was his sister was actually his mother, and the people he thought were his parents were actually his grandparents.
- Kathy Bates waited until 2009, when she had been in remission for five years, to announce that she'd had ovarian cancer.
- The world was surprised when Sandra Bullock introduced her baby boy, which she didn't announce until four years after starting the adoption process and four months after Louis Bardo Bullock was born.
- Sofia Vergara announced in 2008 that she'd had thyroid cancer in 2000.
- In 2004, it was revealed that then-15-year-old model Daisy Lowe was fathered by Gavin Rossdale, who'd briefly been involved with Pearl Lowe as a teenager.
Click for the complete list, which includes more than a few secret babies
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