Pop singer Jessica Simpson and fiance Eric Johnson are excited to be parents, but there's one important matter the couple can't seem to agree on: the sex of their child.

I think it's a girl, Simpson, 31, told People Magazine at the launch of her new clothing line co-created with sister Ashlee Simpson. But I don't know yet.

Johnson, however, seems to have a different opinion.

I think it's a boy, the 32-year old former NFL player said. We're pretty much at a standstill there.

It seems they need to settle the score.

If it's a boy, she joked, I'll put him in tutus!

The couple says they have every intention of finding out the baby's gender.

I don't think we can wait, Johnson said. Jessica is too honest about everything, she needs to know. I don't think she can hold that secret to herself.

Simpson and Johnson won't have to wait long. The couple will find out their baby's gender on Monday, she told the style Web site Fashionista.com.

I find out on Monday, she told the Web site. I can't wait to go home to find out!