(LOS ANGELES) -- Pregnant Jessica Simpson inadvertently revealed she's expecting a boy on Wednesday's edition of ABC's Jimmy Kimmel Live!
While discussing how her second pregnancy has been more difficult than her first, including more vomiting, she blurted out, "The crazy thing is, I never knew a wiener could actually make me nauseous."
After disclosing the baby's gender, she said, "Well I guess I just told the world that I'm having a boy!"
Host Jimmy Kimmel, who initially didn't realize her slip-up, joked, "I didn't even know what was happening. ...I thought maybe you were having a girl with a penis."
Simpson later said, "I can't believe I did that. That was not planned."
When Kimmel asked her about the rumors that she'll name the baby Ace, she attempted to backtrack by declaring, "Let's hope it's a boy!"
Simpson and fiancé Eric Johnson welcomed daughter Maxwell Drew Johnson last May. She announced her latest pregnancy last Christmas Day.
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