Joe Don Rooney's family expanding! The Rascal Flatts star is expecting his third child next month, and he -- and his wife and kids -- are busy preparing for the impending arrival.

Rooney and his wife, Tiffany, will soon welcome their second girl, due Sept. 25. The singer confirmed the news of Tiffany's pregnancy earlier this year, but apparently, the couple still haven't decided on a name.

"We haven’t named her yet, but we’re just very excited," Rooney tells Country Weekly. "I'm just excited to have my wife back, bless her heart. She doesn’t do prego real well. She's been really sick with this one. She’s starting to feel a little better; she’s just in that uncomfortable stage now. But we're really excited."

Rooney's schedule with Rascal Flatts is busy, so he's hoping his daughter's birth happens on an off day. "Our schedule is so crazy. I have like literally a window of time from September 22 through September 26 off, so we’re hoping [her birth] falls in that window," he shares. "No pressure, Tiff!”

With the new addition, the Rascal Flatts family grows, too. Rooney already has a son, Jagger, and a daughter, Raquel. Bandmate Gary LeVox has two daughters who are 10 and 14, and Jay DeMarcus also has two kids.

"It’s crazy in the Rascal Flatts households," DeMarcus says. “We don’t get any sleep on the road or at home!”

The trio is heading to Detroit for a show on Sept. 21 -- just days before Rooney's daughter's due date. Last time the group was in Detroit, another baby was born!

"Last year, Jay’s son was born while we were in Detroit, so we had to fly back that morning to be there for the birth of his son," Rooney explains. "It would be ironic if that happens for me!"

We'll keep our fingers crossed that Baby Girl Rooney waits until dad gets home to show up.

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