Tim McGraw may have signed up for more than he realized when he reached out to a 94-year-old superfan and promised tickets to an April show in South Carolina. Tia Pettygrue says her grandmother is already planning her outfit for the stop on the Soul2Soul Tour.

"She said, 'If I get to give Tim a hug, you think Faith will be mad?'" Pettygrue tells Taste of Country, laughing. "I said, 'I don't think so, Grandma.'"

"She says, 'OK, because I wouldn't care anyway.'"

Courtesy of Tia Pettygrue

Grandma Mary is a longtime country fan and an especially big fan of McGraw's music. She keeps up with new artists and songs on FM and satellite radio. "Humble and Kind" is a recent favorite of hers, but she loves all of the singer's hits. When McGraw and wife Faith Hill announced their 65-date (and counting) tour earlier this month Pettygrue set about getting tickets. However, the best seats were out of their price range. She shared her grandmother's story on Facebook and asked for help. Somehow the story got to McGraw's team, who contacted her on Facebook.

"I thought it was a scam," Pettygrue says with another laugh. McGraw's team promised good seats for the April 20 show in Charleston, S.C., one day before Grandma's 95th birthday. When the "How I'll Always Be" singer came to town five years ago the family was set to attend the show, but Grandma Mary suffered a stroke days before the concert. She's now 100 percent healthy, and will stop at nothing to slip on her cowboy boots for McGraw's concert. Pettygrue describes her as a woman you don't forget.

"She will tell you off in a minute," she shares, laughing. "You can't put anything past her. She will make you laugh so much."

"Everyone that meets her, you just start calling her Grandma. She makes a friend wherever you go."

McGraw further recognized Grandma Mary when he shared Pettygrue's post on his Facebook account, saying, "I think we've got a hook up. Faith Hill and I would love to celebrate with you and your grandmother in Charleston. Come on!"

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