Kevork Djansezian, Getty Images
Last night on 'Jimmy Kimmel Live," however, the singer let some very important information slip -- the gender of her baby!
When asked how she's feeling, Jess admitted she's not so great this this time around.
"The crazy thing is I never knew a wiener could actually make me nauseous," she said, pausing a beat before realizing she just revealed she's having a boy.
Jessica laughed off the mistake, saying, "Well, I guess I just told the whole world I'm having a boy!"
"I didn't even know what was happening," Jimmy quipped. "I thought maybe you were having a girl with a penis."
The boy, who is rumored to be named Ace, will be Jessica's second child with fiance Eric Johnson. The couple already have a daughter, Maxwell, who is 10 months old.
Watch "Jessica Simpson on 'Jimmy Kimmel Live' PART 1" Video
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