A video demonstrating how far a little TLC can go—even in the animal kingdom—has gone viral, racking up over 3 million views on Instagram.

Nathalie Mellaerts, a proud dog owner of 11, recently welcomed a 3-year-old Jack Russell terrier and Chihuahua mix into her life, mostly to keep Billy, her 16-year-old dog company.

In the heartwarming footage shared by @nayatribe, Mellaerts points out that she feared Billy's health may deteriorate after the dog's son passed away, which is why she was prompted to rescue Nugget. Indeed, it worked, as the video shows how Nugget's presence made something "unbelievable" happen.

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The June 9 video shows the inseparable pair playing together and, most importantly, tucking into their food. The on-screen text states, "My sick old dog finally started eating again," followed by, "Her happiness and energy came back, and she's doing so much better because of him [nugget]."

In the caption, Mellaerts explains that she feared losing her beloved senior dog. She wrote: "I wanted another small dog in the future, and I wanted this dog to have known her, to have been taught by her, to somehow be connected to her."

According to research published in Evolution, Medicine, and Public Health, dogs that live in households with other dogs or pets are significantly healthier than those with fewer household companions. The study found that dogs in multi-pet households had higher reported health scores and fewer disease diagnoses compared to dogs with fewer companions.

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This suggests that social enrichment from living with other pets confers substantial health benefits, outweighing the effects of financial factors fivefold.

This is somewhat true for these dogs, but Mellaerts has recently discovered that Nugget isn't as healthy as she thought. In another video, she said that he was diagnosed with leishmaniasis, a disease caused by a protozoan parasite found in dogs, cats, and certain rodents in many parts of the world, most commonly in rural areas. According to the VCA Animal Hospital, the parasite is transmitted by small, biting sand flies.

An excerpt from the heartbreaking caption says, "[He was] previously neglected and abused. He deserves a chance to be happy and healthy. In the past months, I've come to love him so much and I'm already so attached to him."

It isn't just the owner who is worried, but Billy too. In the original video's caption, she wrote: "Nugget being this sick, and now blind, clearly upsets her. She follows me around when I carry him, she only wants to eat when he is eating next to her, she looks for him when he is at the hospital.

"I thought Billy was the one I needed to be worried about, but now I'm terrified of losing both Nugget and her. He needs to get better. He needs to make it, because he deserves a happy, long life - and for her."

Instagram Reacts

So far, the video has received over 1,100 comments, many from pet owners sharing similar experiences.

"Yes my baby boy fluffy (may he rip) went on to live 10 more years after we initially thought we was going to cross the rainbow bridge. All because of our youngest Toto (now 10 years old)," said one user.

"That happened to my senior dog as well. He lasted much longer after we got our youngest! It rejuvenated him," another person wrote.

"You got her [a] soul dog," said a third user.

Newsweek reached out to Nathalie Mellaerts for comment.

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