Tim McGraw and Faith Hill turned to social media on Tuesday (May 5) to wish their oldest daughter, Gracie, a happy birthday in a pair of very sweet messages.

Gracie McGraw turned 23 on Tuesday, and her proud father marked the occasion by sharing a picture of his daughter smiling into the camera. He marveled at the fact that the couple's oldest daughter is already 23, praising Gracie as having "the sweetest, kindest heart in the world....so beautiful inside and out."

"She's always there for her friends. Always there for her family. And always there with a big smile and a boisterous laugh," he writes, adding, "We love her so much."

Hill posted two separate pictures of her daughter on her Instagram, beginning with one of her as a child, adorably dressed in her favorite overalls. She's standing on the bathroom counter in the photo, with McGraw's mom visible behind her in the mirror.

"When you wake up on the day your oldest daughter has just turned 23 years old and you find this photo that shows just how fast time flies," Hill writes. "I don’t have the words.....This photo just brought me to tears."

She added another picture of Gracie today, calling her "a young woman who is simply extraordinary in every way imaginable" and wishing her a happy birthday.

McGraw and Hill married in October of 1996, and the superstar couple welcomed Gracie in May of 1997. Sister Maggie followed in 1998, and the couple welcomed their third and final daughter, Audrey, in 2001.

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