Bill Murray Celebrated Stranger's 94th Birthday With Surprise Serenade: 'It Made Her Day'

Days later, grandma Maryellen Hook Wimble called her grandson and asked if he had Bill Murray's address. "I want to send him a thank you letter," she said.

A 94th birthday is a special occasion, and it seemed like actor Bill Murray agreed when he decided to celebrate the stranger's milestone by serenading her with a rendition of "Happy Birthday" after a Texas college basketball game.

Read: For the Love of Cubs: Bill Murray Makes Fan's Night as He Treats Her to World Series Ticket

"It made her day," said Noah Wible, 24, who joined the actor in singing to his grandmother last weekend.

Wible told InsideEdition.com that the family was out celebrating grandma Maryellen Hook Wible's 94th birthday at a college basketball game, when they saw Bill Murray in the arena.

Wible approached the actor, who was already surrounded by many other fans, and asked if he could take a picture with her for her birthday, he said Murray instead responded, "I think we should sing 'Happy Birthday,' don't you?"

The crowd of 100 fans even joined in as the Groundhog Day star serenaded her for her big day.

"It was incredible. It's awesome he did that for her," Wimble said. He admitted grandma Maryellen was not too familiar with Murray's movies, but "of course she knows who he is now, and she's honored by him."

Days later, Wimble said his grandmother even called to ask if he had Murray's address. "I really want to send him a thank you letter for what he did for me," she told Wimble.

"She was super excited just to be able to leave the house," Wimble said. "My grandmother doesn't get out as much anymore. She's up there in age."

And that was exactly why Wimble and his father wanted to surprise grandmother Maryellen with courtside seats to the Baylor University men's basketball game for her 94th birthday.

"She's a huge basketball fan, and she's also a Baylor fan," he said.

To grandmother Maryellen's delight and Bill Murray's loss, the game ended in a victory for Baylor University. Murray's son is an assistant coach to the opposing team, Xavier College. 

Read: Bill Murray Looks Heartbroken After His Son's Team Loses NCAA Game

The outing was also a way to help get her mind off the one year anniversary of her husband's death.

"It's been lonely for her because she's been married 72 years, and my grandfather passed away last year around this time," he said. "It's been difficult. She said she's been feeling lonely, [but she's] okay. She's an independent woman. She's strong." 

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