Bentonville, Arkansas - An Arkansas animal shelter experienced a magical moment when a deserving dog finally found a forever home after a long wait. His reaction is everything!

A video posted by the Best Friends Animal Society shows one-year-old Eugene with an almost human smile on his face as he is cuddled by his new owner.

"Hello hello I know. I told you. I told you I would come back," the woman tells Eugene.

As the facility reveals, the two already knew each other quite well.

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The former stray dog had not had an easy life, having already spent months in an animal shelter in Jacksonville before being brought to the Best Friends Pet Resource Center in Bentonville, Arkansas.

There, he met foster parents Jason and Nikki, who decided to take Eugene in over the holidays.

The couple immediately fell in love with the dog, but also wanted to give him the chance of a permanent home, so they brought Eugene back to the shelter – but not without making a heartfelt promise first.

"She told him that if he wasn't adopted during Christmas, she would come back for him to make him part of her family for good," Best Friends Animal Society revealed.

That promise was well and truly kept, and as the Instagram post says, "Eugene's smile says it all!"