New York - A baby's laugh is always infectious, and a sugar-sweet viral video shared by a new mom proves that it isn't just humans who feel this way!

In the TikTok clip, a dog named Theo sits on the couch with his little sister, Clara.

The four-legged friend repeatedly pretends to bite the tiny human's hand and arm, but he proceeds very gently and only nibbles lightly.

Clara can hardly contain her laughter and giggles incessantly as the poodle mix fools around with her.

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It's fascinating to see how carefully Theo handles the baby – after all, he's in play mode himself and certainly has to be very careful not to get too excited!

Again and again, the four-legged friend seems to scan Clara's facial expressions to make sure the child doesn't get too wild or feel any pain.

As mom Kate Groth documented on her TikTok page, Clara and Theo have developed an inseparable bond, and it's one that began when the girl was still in her mom's belly!

Since the baby's birth, the dog has hardly left Clara's side, keeping watch over her bed, cuddling with her, or making her laugh, as in the latest viral video.

It's as if the two are real siblings who don't want to be without each other!

Although the friendship between baby and dog is more than cute, parents should still always be present when their four-legged friend and child interact.

On the one hand, even the best-trained dog is still an unpredictable animal, and on the other, babies should not be licked by the furry friends, as they can have bacteria in their saliva that an infant with an immature immune system cannot yet cope with.