Baby number two is on the way for Nick and Vanessa Lachey. 

The couple announced that they are expecting their second child - making their 22-month-old son Camden John a big brother, People Magazine reported. Nick took to Twitter to unveil the big news, and to reveal the baby's gender.

"Can't think of a better way to celebrate 3 years of marriage to my beautiful Vanessa than this," the 40-year-old singer tweeted, along with a picture of Camden running on the beach around a heart in the sand that read, "It's a girl."

In November, Nick called parenthood "the most amazing experience you could ever go through." The lovebirds have been open about wanting to expand their family.

"I do want a girl. I think there's something emotional about having a daughter that I definitely want to experience," he told People in February. "Maybe I'll get one more boy under my belt first. I'll need some help to keep her in line, so a couple of brothers couldn't hurt."

The pair married in July 2011 and welcomed their son in September 2012. After giving birth, the 33-year-old former "TRL" host admitted that she dealt with emotional struggles, in a blog post entitled "Inside Story: My Experience with Baby Blues."

"No matter how many books you read, NOTHING prepares you better than the real thing," she wrote. "I felt lost, unloved, alone and at my wits end... I didn't feel like myself. Where was the super woman who always thought and knew she could do it all? Where was the organized Vanessa who had it all under control no matter what the obstacle? She was gone, and I thought... forever."

The news comes just nearly two weeks after Nick's ex-wife Jessica Simpson tied the knot with Eric Johnson in a lavish ceremony outside Santa Barbara.