AUGUSTA, Ga. -- (CBS NEWS) Not long ago, in a cemetery outside Augusta, Georgia, a loving couple was buried. The wife buried below a white bouquet, the husband buried above, in a mound of grief.

Dan Peterson, 82, said after Mary died, he fell into a deep depression.

“Took me totally by surprise,” he said.

He spent days just staring out at the squirrels from his porch, and he could not figure out what he was living for, other than just waiting to die.

For six months, it was just that bad.

But it all changed inside Dan’s local Publix grocery store.

Dan was nearing the end of the canned vegetable aisle. He hates grocery shopping and, by all accounts, the expression on his face confirmed his aggravation. 

But that’s when this unapproachable man was approached by a four-year-old girl named Norah Wood.

In the security footage Norah can be seen randomly reaching out to him out. Her mom Tara said it was quite embarrassing.

“She stood up and said, ‘Hi old person, it’s my birthday today’” Tara said.

And then she had the audacity to demand a hug.

“I said, ‘A hug?!’ I said, ‘Absolutely!’” Dan said.

Norah got her hug and then asked her mom to take a picture of her with her new friend.

“She zeroed in on him like a missile. And she didn’t want anything from him,” Tara said. “She just wanted to make him feel loved and give him a hug. And his little lip quivered and he was teared up and it was just sweet.”

“And I said, ‘You don’t know. This is the first time, for quite a while, that I’ve been this happy,’” Dan said.

That all happened back in September, and his grin has only gotten wider since.

Today Norah visits at least once a week, and every time it’s the grocery store all over again.

Their last visit was over Christmas. He got her some dress up clothes, and she got him a gallery of framed photos.

By the way, Dan does have grandkids of his own, but they’re all grown and gone. And Norah does have grandparents, but her mom says this is a completely different kind of bond that almost defies explanation.

“She fell asleep holding a picture of them. And I’m like, ‘what!?’” Tara said.

To Dan, it’s equally miraculous but far less mysterious. He believes Norah is, quite literally, an angel.

“She opened me to a love that I didn’t know existed,” Dan said.

Does he feel like he has a purpose now, after his wife’s death?

“Of course,” Dan said. “Norah, watching her grow up. I know I made room in my heart for a lot more.”

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