Reaching your 100th birthday? Amazing.

Getting "The Rock" to serenade you with Happy Birthday? Priceless.

Dwayne Johnson surprised Marie Grover with a special birthday message after learning through the social media grapevine that she's been a fan of his since his WWE days 25 years ago.

Jamie Klingler, a friend of the family, told BuzzFeed News that she had been working to get in touch with Johnson's publicist to send a shout-out to the centenarian.

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Klingler posted to Twitter that she was working on this.

"She will lose her mind. When we were in high school (25 years ago) she would wear a rock sweat shirt and tell us how handsome he is," Klingler wrote.

Johnson saw it and responded.

"What?? First I’m hearing of this! Who’s turning 100? Beautiful age! What do you need, Jamie?" Johnson replied.

Johnson filmed a video of himself singing Happy Birthday and sending out a message of love to Grover. 

"I'm sending you so much love and a huge congratulations on 100 years. What an amazing life," Johnson said.

Klingler posted a side-by-side video of Johnson's message and Grover's joyous response.

Johnson retweeted the video, saying doing things like that are the best part of being famous.

"It’s really all down to Dwayne and his kindness," Klingler told BuzzFeed. "He made an old woman so incredibly happy. I will always be grateful. She is a legend."