Allentown, Pennsylvania - For six months, golden retriever brothers Finnley and Jet grew up side by side. After the dogs were adopted by different families and separated, their viral reunion has warmed hearts worldwide.

Finnley, who has become a star on TikTok, was taken to the park by his owner for a walk. What the four-legged friend didn't know was that a very special surprise was waiting for him on the way.

"They had not seen each other in over a month," Finnley's owner from Allentown, Pennsylvania, wrote on TikTok of the seven-month-old pups from the same litter. "So we arranged an 'accidental' run-in to see if the brothers would recognize each other on their own, with no cues while crossing paths."

The pet owner captured the moment the two dogs met on video. In the clip, the animals can be seen approaching each other tentatively at first. But seconds later, their tails start wagging, and they cuddle and play.

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"Within seconds they were back to being inseparable as if they’d never been apart," she wrote.

"The bond between Finn and Jet is still as strong as ever and its so sweet wholesome each time we watch these two play their little puppy hearts out."

According to PetHelpful, studies have shown that puppies who have been allowed to stay with their animal family for at least four months can still recognize their mother's scent for up to two years, and their siblings. And the other way around, too.

"The way they immediately knew," one viewer commented.

The clip of the two pups has been viewed 1.6 million times and counting on TikTok.