Pink and Husband Carey Hart Expecting 2nd Child

— -- Now we know what Pink has been doing since she's been out of the spotlight: She revealed today that she and husband Carey Hart are expecting their second child.

Pink, 37, announced the news by sharing a photo on Twitter of herself with the couple's 5-year-old daughter, Willow. Pink appears extremely pregnant, and Willow is resting her head on her mom's belly. The caption reads, "Surprise!"

Ever since Pink, born Alecia Moore, and Carey, 41, welcomed Willow in 2011, the singer has been talking about the possibility of expanding her family.

She told "Good Morning America" earlier this year, "I love being a mama. I made a choice a long time ago that I was going to have a successful family and that is my absolute No. 1 goal in life."

The two wed in 2006.

While Pink has been laying low, she's still dominating the charts. Her song "Just Like Fire," from the movie "Alice Through the Looking Glass," was a huge hit, and she also topped the country charts with "Setting the World on Fire," her duet with country superstar Kenny Chesney.