These two Dalmatian siblings are one heart and soul, as Luna and Lacy do everything together. And if her little sister has a bad nightmare, Lacy is always there to look out for her. But do dogs dream?

The sweet interaction of these two dogs is a dream - and currently delighting the internet.

Lacy and her little sister Luna live under the same roof, and they're always up to something together.

As seen in one of their interactions that has gone viral on TikTok, the pups were dozing peacefully on the sofa when Luna suddenly began to squeak, pant, and flinch in her sleep.

Cats Getting along like cats and dogs: Hysterical animal duo has TikTok cracking up

Clearly, the pooch was suffering a bad nightmare.

Lacy showed concern, turned around, and looked at her little sister for a quite some time. Only when the caring dog was convinced that her little sister was "just" dreaming did she turn her attention back to her own snoozing.

"Your little sister is having wild dreams, and you need to check off to make sure she's okay," their owner wrote in a caption of the video showing the sweet moment.

The cute TikTok video has already been viewed more than 506,000 times and users are delighted, with many commenting on their "true dog love."

Just like us humans, man's best friend can also dream. Some scientists are even convinced that dogs have much more intense dream experiences.

Pups go through the same sleep phases as we do - falling asleep, light sleep, deep sleep, and REM sleep. While humans usually go through about five sleep cycles, however, dogs can go through up to 20 cycles.

In between, they have short periods of wakefulness, an inheritance from their wolf ancestry, animal experts note. This allows them to check whether their sleeping place is still safe.

Animal World Records This giant rodent is as big as a wolf!

But what do dogs dream about? Researchers believe dogs process the events of the previous day in their dreams. Common dreams include eating, toys, and interactions with their owner. Whether dogs remember their dreams has yet to be researched.

Nightmares are thought to occur from time to time, just like in humans. Some animals may whimper, wince, or kick in their sleep. In the case of a nightmare, it is better not to wake a dog, as this could frighten them even more.

Animal activists recommend: "If you notice that your dog is having a nightmare, you should gently put your hand on his belly. Talk to them in a low voice. Ideally, they will then not wake up, but calm down again."

You can help your pup by making sure they have a comfy place to catch some ZZZ's, just like Luna and Lacy!