Mister Rogers would be so proud.
Hearts across America soared when the story of 2-year-old Benjamin Olson becoming best friends during the pandemic with his next-door neighbor, 99-year-old Mary O'Neill, went viral.
“For more than a year, he didn’t see other kids. He didn’t interact with anyone except our family and Mary,” Benjamin’s mom, Sarah Olson of Minnesota, told TODAY Parents earlier this year. “They ended up forming an incredibly strong bond.”
But the pandemic-made pair recently had something new to celebrate: Mary's 100th birthday.
To mark the occasion, friends and family gathered early to celebrate O'Neill's milestone, which will become official on Dec. 18.
"It is his buddy and he was very excited to go to her party," Olson told TODAY. "A lot of her family has been hearing about Benjamin so they were excited to meet him. (Their friendship) just added a really special layer to her party."

One party guest gifted the centenarian a bag of treats.
"Mary's niece gave her a bag of treats for Benjamin to share during playtime," Olson said. "Now pretty much every day, we see Mary and she asks, 'Is it snack time? Can I bring him a snack?'"
The Olson family celebrated their beloved neighbor in a special way.
"After the first story aired, everybody was so excited about it," Olson said. "I set a goal of getting 100 birthday cards for Mary's 100th birthday and set up P.O. Box."
Through word of mouth, news of Olson's birthday card goal spread.
"It turned into 300 cards from 21 states, plus a card from Germany," Olson said.

The mom of two shared that little Benjamin was excited to celebrate his "Mimi," a name he coined for O'Neill since their friendship began.
"Most of his friendship with Mary, he didn't really say a lot of words," Olson explained. "For him to come up with Mimi was really cute. Now she's just Mimi and he asks for Mimi all day long."
In an interview with NBC affiliate KARE 11, O'Neill's daughter, Sui Curtis, said she believes the friendship was meant to be.
“She was sitting doing nothing and Benjamin was sent to her to make her move and make her go,” Curtis shared.
That sentiment is not lost on Olson.
"I've been so surprised to learn how much he meant to her. I had never thought about it or considered it," she said. "I just thought it was two cute people hanging out together. To know that it's had such a big impact on her is special."

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