Looks like Garth Brooks' tour is becoming a family affair. The singer, who is already joined on the road by his wife Trisha Yearwood, also had the company of his youngest daughter Allie, who just graduated high school this past June, at a recent show.

The teenager sang as part of his backing band for his show in Chicago on Sunday (Sept. 14), along with his three usual vocalists, dubbed the Wall of Sound, for the entire two-hour show.

"We've been working together for, I don't know, the last 18 years now or so," he told the crowd as he was introducing his band (quote via CMT). "This little girl's very talented. She does background vocals, acoustic guitar, singer-songwriter. From Owasso, Oklahoma, give it up for Miss Allie Colleen."

Allie is the youngest of three daughters Brooks had with his first wife, Sandy. It is fitting that the young woman joined him on stage, since when he famously came off the road in 2000, he said he wouldn't return to touring until his youngest daughter graduated from high school.

The 'Friends in Low Places' singer isn't surprised by his youngest child's interest in performing.

“My youngest has got it,” Brooks has said. “She’s got the bug, but she’s got the goods, too. She starts playing and singing, I have to get up and leave because I spent my whole life crying.”

No word yet if his daughter will continue on the road with her father. Brooks will head to Atlanta, Ga., on Friday night (Sept. 19) for a series of seven shows. Keep track of tour updates here.

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