Zac Brown is about to be even more outnumbered at home. The Best New Artist Grammy winner and his wife, Shelly, are expecting their fourth daughter in four years.

People magazine reports that the baby is due early next year. She will join sisters Justice, 3, Lucy, 2, and Georgia Sloan, 11 months.

There must be something in the water on the Zac Brown Band tour bus, because fiddle player Jimmy De Martini and his wife are also expecting a baby! There's no word yet on whether they've found out their baby's gender.

The Zac Brown Band's new album, 'You Get What You Give,' is set to hit stores September 21. Guest musicians on the project include famed bluegrass guitarist Tony Rice, Jimmy Buffett and Alan Jackson, who's featured on the first single, 'As She's Walking Away.'

The Zac Brown Band are currently on tour previewing songs from the new project. After playing several shows with the Dave Matthews Band, they'll trade the road for the water, leaving on their Sailing Southern Ground Cruise next Thursday, September 2. The "floating festival" goes from Tampa, Fla. to Grand Cayman and includes nightly concerts and lots of Zac's own famous home cooking.