"And then there was one."
Man in Restaurant
Credit: Hoxton/Tom Merton/Getty Images

Over the past seven years or so, Brandt Barber and his three sons developed a bit of a weekly tradition. They would go to the same Dairy Queen in Forsyth County, Georgia, sit in the same booth, and order the same things from the same little old lady.

It's a ritual that began to take on more meaning as the boys began leaving for college. Brooks, the oldest, was the first to depart a few years ago, and then last month his twin 19-year-old sons Bryce and Luke also headed off for college.

Feeling sentimental and nostalgic, Brandt, 57, took to Instagram to share a series of photos he took of himself and his sons in their Dairy Queen booth over the years.

The final photo was of Brandt sitting alone in the booth. "And then there was 1," he wrote in the caption, adding that the tradition was never just about ice cream, but the time spent "talking" and bonding.

"Over time the most valuable part of it was [spending] time with the boys," Brandt told Buzzfeed. "I'm talking to them, they're talking to me, we're listening to their music, they're talking about girlfriends... just life. It gave us time for that, which was awesome."

Although Brandt originally shared the post with just friends and family on his private Instagram account, Brooks, overcome with emotion himself, shared screenshots of his dad's post on Twitter (below). Brooks' tweet quickly went viral and has garnered more than 165,000 shares since August 30.

Brandt's sweet, emotional reflection on fatherhood has touched strangers all over the world.

He told Buzzfeed that he's received countless messages from strangers sharing their stories about their own complicated relationships with their dads. He said he's trying to respond to as many of those messages as he can.

"I've looked at this as, OK, how can I be responsible in communicating back with some of these folks and be encouraging and uplifting to them," he said.

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Brandt encourages them to grow up to be the parents they were deprived of.

"You have a chance with your young son to change how it was, and honestly, I did," Brandt concluded. "Don't let your circumstances define you. You find your own happiness."