Jessica Simpson will find out the gender of her baby on Monday, but the singer took a guess last night at the launch of her sister's clothing line in New York City.

"I think it' a girl," the pregnant star told People, while fiance Eric Johnson chimed in with: "I think it's a boy."

One of them will probably be correct.

Why is Jessica - seen above getting some practice in with nephew Bronx - even learning her first child's sex ahead of time?

"I like to plan things out," Simpson told Us Weekly at the same event. "It'll be good to know what colors to make the nursery. I'm obsessed with thinking about what it's going to look like."

We're just glad there are no signs here of a pregnancy in crisis, as a recent report claimed. Quite the opposite, in fact, as Simpson gushed last night over "knowing that [Eric] and I created something inside of me... We love each other so much, and knowing that I love this baby inside of me is so amazing."

[Photo: WENN.com]