On Monday, Sept. 1, the singer-songwriter tweeted a picture with her dogs, Ace and Penny, wearing shirts announcing they were going to be big siblings.
Underwood's hubby of four years, NHL player Mike Fisher, also tweeted the couple's big news, jokingly stating they're expecting another dog.
No word yet on whether the pair will be expecting a little cowboy or cowgirl, but congratulations all the same!