The Civil Wars' Joy Williams Is Pregnant
02/13/2012 AT 01:15 PM EST
The duo's female half, Joy Williams, announced her pregnancy on Friday by Tweeting, "Beyond elated to share that [husband] Nate [Yetton] & I are expecting our first child in late June!!! My baby bump & I will see you on the red carpet."
Williams, 29, and partner John Paul White picked up awards for best folk album and best country duo/group performance at Sunday's show.
"I'm feeling butterflies but I can't tell if it's my baby kicking or the actual butterflies itself," she said backstage, joking that she's a "human bakery". "Both sensations are really, really wonderful."
Williams and White, who formed their band in 2008, hit the public eye when their song "Poison & Wine" was featured on Grey's Anatomy.
Widening their audience with a 2011 stint opening for big Grammy winner Adele, the duo performed their hit "Barton Hollow" on the Staples Center stage before introducing pal Taylor Swift.
The Civil Wars collaborated with the singer and composer T-Bone Burnett for "Safe & Sound," the first song from The Hunger Games soundtrack, premiering Monday evening on MTV.