Nick and Vanessa Lachey

It's what Nick Lachey has always wanted. His wife, Vanessa Lachey, is pregnant.

The baby is due in late summer or early fall.

She started to feel a little different, not herself, Lachey said on the show. So she went to the store, got a pregnancy test, and it came back positive. So we are having a baby!

I've had a chance to do a lot of great things in my career and my life but this is the one thing that, more than any other, I look forward to, he continued. The fact that it's actually here, it's overwhelming.

The couple does not yet know the sex of the baby, but they do plan on finding out.

We definitely want to know, Lachey said. I can't take the knowledge that someone out there knows, but I don't know. It's like watching a sports game on TiVo.

If it's a girl, I think it might be Sophia, he continued. If it's a boy, I'm not sure.

Lachey also says that he has no problem tending to his expectant wife and her needs.

I'm the one running in the middle of the night to the restaurants to get her whatever she needs, he said. She loves; she craves Mexican food right now. She could eat a burrito a day so you can imagine what our house smells like right about now.

Vanessa Lachey has not commented about the pregnancy yet, but spoke to People Magazine last year about her desire to have children.

I would love to have children and work, Lachey said. I definitely don't want it to slow me down. I'm always going to be, 'Go, go, go.' And I'm going to be pregnant, fat and happy through it all.