Tim McGraw turned to social media to wish his daughter Maggie a happy 19th birthday, accompanied by an adorable photo of the girl scuba diving.

"Happy birthday Mags-a-million," McGraw captions the Instagram photo above, which shows his middle daughter in full scuba gear, looking at the camera as a full array of ocean life is visible behind her. "Ur sisters, your mom and I are so proud of you and your adventurous spirit..... Stay curious! we love you!"

McGraw and his wife Faith Hill are pretty private about their kids, but as they've gotten older the couple have opened up more about posting pictures with them. McGraw even took Maggie to the American Music Awards as his date in 2016 and posted a picture to Facebook.

See Tim and Faith's Best Photos Through the Years

McGraw and Hill married in 1996 and had their oldest daughter, Gracie, in 1997. Maggie followed in 1998, with the couple's youngest daughter, Audrey, born in 2001. Gracie is away at college and also has a band, and she joined McGraw onstage at his Nashville show in 2015 to sing "Here Tonight."

Maggie also left for college in 2016, with Hill taking her middle daughter on a cross-country road trip as she made the transition and sharing precious photos via social media along the way.

The couple admit it was hard to say goodbye to their daughters when the time came for them to leave the nest.

“It was painful,” McGraw tells 99.5 WYCD. “But, in a way it made us sad, but made us happy as well.”

“When we were moving Maggie into her dorm — and the same thing happened with Gracie when we moved her into her dorm when she went to school — I mean, 30 minutes after being in there and moving things in they were trying to kick us out,” he shares.

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