Carrie Underwood made the ultimate Labor Day pun on Monday (September 1) when she announced her pregnancy on Twitter. The country star cuddled up with her two dogs, who were wearing "I'm going to be a big brother/sister" shirts. Couldn't get any cuter.

"In honor of 'Labor' Day...Ace & Penny would like to make an announcement. Their parents couldn't be happier!" she wrote.

Underwood is expecting with husband Mike Fisher, a NHL player for the Nashville Predators. After two years of dating (they met at one of her concerts in 2008 in Toronto), the couple married in 2010.