Thompson Square are officially a trio: Keifer and Shawna Thompson have welcomed their first child, a son.

E! News reports that Rigney Cooper Thompson was born on Sunday (Jan. 24) at 2:46 AM. Baby Rigney came into the world weighing 7 pounds and 13 ounces and measuring 19 inches long; he has brown hair and brown eyes.

"It's hard to explain this kind of love," the couple says. "We're so overjoyed. He's already got us wrapped around his little finger."

The baby's first name is Shawna Thompson's grandmother's maiden name.

“We've had many wonderful things happen to us, but this absolutely tops them all," the Thompsons share on Instagram, along with a photo of all three of them. "We want to thank you all for being there for us and our music, and for all of your support during our pregnancy. We can't wait to see you out on the road this year, but until then ... please say hello and welcome to this big ol' world, Rigney Cooper Thompson, aka #coopert #cooperman #coopdeville #coopdog #sircoopsalot."

Thompson Square first revealed that they were expecting a baby back in August. In September, they shared the news that they would be having a baby boy.

“We’ve been together for a long time, and we’ve done a lot of things, and we just really felt there was something missing," Keifer Thompson said when the couple announced that their first child was on the way. "We love what we do, we love the music business, but we didn’t want to deprive ourselves of having a family.”

Thompson Square have been married since May of 1999. They first met at a singing competition after they separately moved to Nashville, but they didn’t instantly become a duo.

“... We didn’t realize until a few years into our marriage that the best way for us to coexist was for us to be together all the time,” says Keifer Thompson. “Being apart and doing our own things … we just weren’t happy. We were happy doing music, and the relationship wasn’t suffering, but it wasn’t as good without her.”

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