Kim Zolciak-Biermann's Son Gets Licked by Dog Who Attacked Him Over a Year Ago in New Photo

Kim Zolciak-Biermann and husband Kroy Biermann faced the nightmare of their lives last April when their rescue dog Sinn bit their 5-year-old son Kash, nearly blinding him.

But over a year later, Kash and Sinn are closer than ever, as seen in new photos that Kim posted to Instagram on Tuesday.

“These 2 melt my heart,” Kim captioned the gallery of pictures, which showed the husky-boxer mix licking the smiling boy’s face.

“@kashbiermann loves Sinn so much,” Kim continued. “I was just snapping away a minute ago watching these 2 and here are a couple of them. #TrueLove #BlessedGrateful.”

Kash’s injury, and the Biermanns’ tough decision to keep Sinn in the aftermath, was documented on the sixth season of Don’t Be Tardy — the reality series that follows the Real Housewives of Atlanta star and her life at home with Kroy and their six children.

“It was a like a bad dream,” Kim previously told PEOPLE exclusively of the bite, which left Kash in the hospital for four days as the scratch was a millimeter away from his eye. “Our dog Sinn is heavily, heavily trained. Kash is his favorite. It made absolutely no sense to any of us. This is nothing I ever thought I’d be dealing with in my life.”

At the time of the bite, Kash was playing with Sinn outside alongside the Biermanns’ other son KJ, 7. Nearby, Kroy, 32, was using a leaf blower to clean the yard — a sound which scared Sinn and cause the bite. “Being right there, it was just wrong place, wrong time, wrong circumstances,” Kroy told PEOPLE. “The perfect storm.”

After the incident, Kim and Kroy — who have four other rescue dogs — sent Sinn away from their house to stay with their trainer as they debated whether or not to keep the dog. Kroy’s instinct was to get rid him.

“I hated Sinn,” Kroy said. “I genuinely felt a deep rage for what he had done to my son. Sinn was always a good dog, extremely obedient and protective and not at all aggressive. He’s hyper-active and hyper-sensitive but wants to work and loves to be commanded. I love my dog, and nothing like this had ever happened to me before. But it’s my son. I don’t love anything more than my flesh and blood. I thought, ‘I don’t want to see the dog — he doesn’t get a second chance.’ ”

Complicating matters was the fact that over the years, Sinn had formed an “incredible bond” with Kash. “Sinn and Kash have been best friends since the day we got Sinn,” Kim explained. “Kash is an absolute animal lover, and Sinn is definitely his favorite, without a shadow of a doubt. That’s why it was extra hard.”

“I genuinely felt a deep rage for what Sinn had done to my son, but Kash loves him,” Kroy told PEOPLE.” We didn’t want him to live a life with a phobia of dogs. We wanted him to understand it wasn’t his fault.”

Ultimately, they spoke with nearly a dozen behavioral specialists, child psychologists and dog-bite survivors before deciding what to do. Kash, meanwhile, showed no anxiety or fear about the incident, and even jumped at the chance to see a service dog while in the hospital after one of his multiple surgeries.

RELATED VIDEO: Kim Zolciak-Biermann Surprises Son Kash With Pit Bull Puppy Four Months After Dog Attack

Sinn was eventually let back into the home, with a new routine and a new large fenced-in area to play.

The Biermanns have used the incident as an opportunity to teach their family about the warning signs to look out for if your dog is being aggressive.

“We’ve taught our kids, no matter how nice dogs are, they are capable of anything and cannot communicate to us in another way than through action — be it barking, growling, biting, scratching, or running away,” Kroy told PEOPLE. “A child sees flurry, fluffy, fun, slobbery … they don’t see danger. And we didn’t either, as adults who had always owned dogs but never gone through something like this. But you have to understand those triggers. Whether it’s loud noise, their tail being pulled, whatever it is, it should be on the forefront of everybody’s mind. Not as fear, but just awareness.”