Neil Warner / Splash NewsSometimes when you've got a secret bottled up, you feel like you're about to pop.
Case in point: Kate Middleton's possible baby-girl-revealing slipup. But the royal mom-to-be isn't the first star to inadvertently dish about something she intended to keep private.
Here are five more stars who accidentally spilled baby news!
1. Jessica Simpson: Earlier this week, J.Simp let it slip on Jimmy Kimmel Live that she and fiancé Eric Johnson are expecting a little boy. Jess was telling Jimmy how much she's been vomiting with pregnancy No. 2, then blurted out, "The crazy thing is I never knew a wiener could make me nauseous!" After a little prodding from the late-night host, she finally fessed up. "Well," she said, "I guess I just told the world that I'm having a boy!"
2. Jack Black: Leave it to this guy to spoil someone else's secret! In May 2008, Jack and his Kung Fu Panda costar, Angelina Jolie, were in Cannes promoting the film. While the duo were chatting with Today show's Natalie Morales, Jack tuned to Angelina (then a mom of four) and said, "You're going to have as many as the Brady Bunch when you have these!" Natalie didn't miss a beat, asking Angelina if she was really having twins. "Well, Jack just confirmed it actually," she said laughingly.
3. Jay Cutler's Teammate: Oh, Earl Bennett, this probably wasn't the best way to build up trust in the field. In May 2012, Earl let it slip on The Boers and Bernstein radio show that Jay and fiancé Kristin Cavallari had "a baby on the way—he's having a boy—and you know I'm excited for Jay," Earl blabbed.
4. Ali Larter: While promoting Resident Evil: Afterlife 3-D in September 2010, the actress let it slip that she was expecting a boy. When asked if her future child had a future in video games, she told Fox News, "Well, after watching these movies and hearing all the gunfire I don't know what he's—it's—going to turn out like."
5. Holly Madison's Boyfriend: In October, Pasquale Rotella Instagrammed a photo of his then-pregnant Playboy Playmate girlfriend and their baby's sonogram picture. "Off to Amsterdam," he wrote. "And I already miss my girls." Just a few days later, Holly confirmed the exciting news herself.
Hey, sometimes it's not so bad for happy secrets like these to slip out.