Living with a sibling or two almost always guarantees a fight will break out. It's part of every sibling relationship. That even rings true for doggy siblings.

In a typical sibling manner, two dogs were going at it in a July 12 TikTok video posted to the account @leelee_and_ella. Thinking no one was looking, one golden retriever took the "fighting" to the next level and flashed her teeth at the other dog. However, she retracted that facial expression when she spotted her mom watching them.

Just as quickly as she showed her teeth, the dog covered her teeth back up. She shot the owner an innocent smile, hoping her mastermind plan wasn't revealed.

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Shocked and surprised by the behavior, the owner couldn't believe her eyes. This whole time, the dog put on a persona of being a sweet doggy. It left the owning questioning herself and she asked in the caption: "She's been pretending this whole time?!?!"

But don't stress; the two dogs weren't actually fighting. They were going about their usual playing behavior, the owner told Newsweek via TikTok. She said she'd seen her dog show her teeth like this before. Cracking up every time, she needed to share it with the rest of the world.

The hilarious moment caught on camera quickly went viral on TikTok. As of Tuesday, the clip reached over 12.3 million views, 2.4 million views and nearly 1,800 comments.

"This is so sibling-coded," commented a viewer, while a second person said: "She looked first to make sure you weren't looking." Sounds like a typical sibling.

Another wrote: "Oh, that was slick. I didn't even catch it until you did the slow-mo."

Someone wrote what the golden was likely saying to the other dog: "You're lucky mom is here."

Dogs Showing Teeth While Playing

You're watching your dogs play, and as it intensifies, you start noticing their teeth showing. You begin to worry—has this gone too far? But, just as dogs use their body to communicate, they also use their teeth.

A Vet Explains Pets article shared that dogs show their teeth during play to show excitement and enthusiasm. The rest of their body language will determine whether their teeth showing is a sign of aggression. It is their way of socializing and communicating.

It's natural for dogs to use teeth showing while playing: It's a trait inherited from their ancestors. Wolves would flash their teeth to establish dominance, the article said. While domesticated dogs won't show their teeth for dominance or to assert themselves, the idea is still present in their genes.

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