A dog's attempt at upstaging her owners' baby has delighted viewers online.

The video, posted to TikTok on August 11 by Emily Slayton under @guiltyreese, features the family's chocolate Labrador, Reese, baring her teeth behind the baby in what Slayton jokingly described as a jealous attempt to be cuter than her newborn sibling.

The video has gained significant attention online, amassing over 3.1 million views to date. Viewers have flooded the comments with laughter and intrigue, with many unsure whether Reese's "smile" is a simply a grin or something more serious.

"Our dog Reese is 8 and a half and we've noticed her funny smile since she was a puppy," Slayton told Newsweek. "She does it for all kinds of emotions—happy, excited, guilty, scared.

"People online were concerned she might be having seizures, but our vet assured us it's just her 'submissive smile,' a way to show she means no harm."

"That dog will bite but it's funny video," one viewer had commented.

Another added: "The baby is concerned and so am I."

Viewers were able to see Reese sitting behind the baby, her mouth stretched into what looks like a broad grin, while the baby innocently looks on.

"I think she's jealous," Slayton joked in the video's caption, as viewers couldn't help but laugh at the dog's antics.

Slayton added that Reese's distinctive smile became more frequent after the birth of their first child.

"It really came out when we had our baby," she said. "Whenever the baby is around, Reese does her silly smile. While it may seem aggressive, we know it's Reese telling us, 'I won't cause any harm!' It's actually very sweet how gentle she is with our daughter, and they have grown to have a wonderful friendship."

Reese's viral fame is nothing new. According to Slayton, the dog has had several videos blow up online, each featuring her unique way of expressing emotions.

The family's followers on TikTok have had mixed reactions, with some worrying about Reese's health, while others find her expression endearing and hilarious. The Slaytons, however, are well aware of social media users' tendency to overanalyze.

"We've tried to reassure people that it's just her personality, but you know how the internet is," Slayton said.

"People love to give their opinion, and we try to stay out of the drama. We joke that Reese is our 'internet-famous queen,' and she loves all the attention, treats, and toys that come her way because of it!"

The viral nature of Reese's videos has also opened up new opportunities for the family. Slayton revealed that she and her husband, John, are working on launching a dog product inspired by Reese, which they plan to announce on TikTok.

"It's a product that doesn't exist in the market yet, and we're excited to reveal it when the time comes," she said.

"Our hope is that Reese's fans will support her new business venture and find the product useful!"

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