The family is expanding!

Nick Lachey and wife Vanessa Minnillo are expecting their second child, the former 98 Degrees singer announced on Twitter.

"Can't think of a better way to celebrate 3 years of marriage to my beautiful @VanessaLachey than this! #family," he captioned a photo of the words "It's a girl" written in sand.

The pair are already parents to son Camden, who was born in September 2012.

"[Love for Camden] is just all-encompassing. You would do anything for your children -- not that you wouldn't for your wife or someone else you love but there's a sense of protectiveness and responsibility that comes with your child which you don't feel in any other relationship. He has changed my life in every possible way," the 40-year-old former boybander gushed about parenthood last year to the Huffington Post.

We wonder if they will name her Jessica? Just kidding!