Owner called vet when her pup kept licking her healthy Rottweiler’s shoulder — 3 days later, came a life-changing diagnosis

Dogs have a way of surprising us, sometimes with their goofy behavior, and other times with instincts that seem almost too sharp to be real. While we often laugh off their habits or quirks, there are moments when those little things turn out to be incredibly important. One such story was recently posted by Reddit user u/Lunagalaxy8, whose young dog’s odd behavior ended up playing a key role in a serious health discovery.

She shared that her Husky mix puppy, Spark, had always loved annoying her older Rottweiler. So, when he started licking the older dog’s shoulder nonstop, she didn’t think much of it. "She would grumble as usual, and he would carry on because she’s a Rottweiler, so when doesn’t she grumble?" she wrote. After about two weeks of this persistent licking, she decided to check the area herself. That’s when she felt a tiny, hard lump, something she admitted she never would have noticed if she wasn’t specifically looking. She then revealed, "Over the course of these two weeks, the lump slightly fluctuated in size, which I found very strange and made me assume it was a cyst of some sort."

That's when they called the vet and were scheduled for an appointment in a couple of weeks. What the owner assumed was just a harmless cyst actually turned out to be something far more serious. When the vet finally did a biopsy, the results came back shocking; it was a mast cell tumor. Surgery was quickly scheduled, and thankfully, the entire tumor was removed. "All went well and they managed to remove it all," she said.

Looking back, she credits Spark’s behavior with catching it early. "If it wasn’t for my puppy’s constant licking, I probably wouldn’t have found this for a while, and who knows how much it could have spread by then," she wrote. Her advice to other pet owners is simple but powerful: "If one of your dogs won’t leave a specific part of your other dog alone, don’t ignore it! They might know something you don’t. I’m now hyper aware of any excessive licking from either of them."

The story instantly went viral with many users praising the young canine for his instincts, while also sharing their own experiences. One user, u/HedgieCake372, wrote, "I actually just had something similar happen. A few weeks ago, I introduced my boyfriend’s dog to my hedgehog, and she gradually became obsessed with trying to lick one side of his face. I had attributed it to the excitement of meeting a new animal, but a few days later, I found a lump in his mouth that turned out to be a squamous cell carcinoma. Unfortunately, it was malignant and too late when I found it." 

u/crazydoglady11 added, "I’ve always found it so amazing how dogs can smell cancer. Our boy actually alerted us to our girl dog’s cancer as well. He would obsessively smell her butt whenever he got the chance. At first, we thought it could be a UTI, but came to find out he was actually smelling her lymph nodes (they have them in the backs of their legs) that were enlarged. She’s now going through chemo for lymphoma. He’s definitely the reason why we caught it so fast!"