Nick Lachey, Vanessa Minnillo expecting first child

March 5, 2012 at 10:33 AM ET

Jason Merritt / Getty Images
BEVERLY HILLS, CA - FEBRUARY 12: Singer Nick Lachey (L) and actress Vanessa Minnillo arrives at the 2011 Pre-GRAMMY Gala and Salute To Industry Icons Honoring David Geffen at Beverly Hilton on February 12, 2011 in Beverly Hills, California. (Photo by Jason Merritt/Getty Images)

Vanessa Minnillo and Nick Lachey are expecting their first child, Lachey announced Monday morning on "Live! With Kelly."

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"She's just 12 weeks," a source tells Us Weekly of Minnillo, 30. "They're both thrilled so excited. Can't wait to meet the new little one."

"She was in New York and I was in the Bahamas," Lachey explained on "Live!" of discovering the big news. "She went to the store and got a pregnancy test and it came back positive. We're having a baby!"

Gushed the ecstatic dad-to-be: "This is the one thing that more than any other I've looked forward to, and it's overwhelming."

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The duo aren't yet positive on the names. "If it's a girl, I think it might be Sophia. If it's a boy, I'm not sure."

He noted that Minnillo is "due in late summer, early fall." 

Minnillo offered a sneak peak of her baby bump while vacationing in Cabo San Lucas, Mexico on Feb. 25.

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"It just looked like she had eaten a really big burrito for a while," he joked.

Her cravings? "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."

Lachey added that he is more than happy to tend to his wife's every need: "I'm the one running in the middle of the night to the restaurants to get her whatever she needs."

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Back in August, Lachey, 37, said he was "doing everything I can" to get his wife pregnant.

"Trust me, it would make me very happy," he said. "Family is very important. It's very important to us, and I'm sure that will be around the corner."

The "Wipeout" hostess and "The Sing Off" host wed on Necker Island last July. Lachey's first wife, Jessica Simpson, is due with her own child this spring; the dad is fiance Eric Johnson.

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