Waltham, Massachusetts - Dog-sitter Peli Roja published two videos on her TikTok and Instagram accounts in mid-September showing how a series of sweet doggos reacted before and after being complimented.

The effect on the dogs, you ask? Most, who were straight-faced in the first picture pre-compliment, are seen "smiling" proudly into the camera in the picture after the praise.

The heart-warming contrast between the two shots has brought the posts millions of views!

On TikTok alone, Peli Roja's Pets has reached four million people with her first clip, and as many as 14 million with the second.

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Not every dog is "smiling" after being complimented, however – one pup actually started to get shy after the praise!

In the second video, the dog-sitter shows the reaction of a very good girl named Ruby.

The little pooch is the only one of the dogs who does not "smile" after being praised. Instead, she holds her paws in front of her face bashfully.

"Compliments make Ruby shy," Roja captioned the video.

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"As a [long-time] pet mom, I know how important it is to find good care when you’re away from home," Roja wrote on her business website. "I’m here to love and take care of your pets just as you would if you were home."

There can be little doubt in anyone's mind that Roja chose the right career after watching these touching videos!