Quite possibly the cutest animal on the face of the planet, the Quokka comes from the same family as the kangaroo (called the Macropodidae). They were once found on mainland Western Australia but are now mostly found offshore on Rottnest Island (near Perth) and Bald Island (near Albany). However, there are still a few isolated groups inhabiting the bushland that surround the city of Perth and the mainland.
Quokkas are known as the world’s happiest animal because of their smile! It looks like they are saying cheese to the camera when you take a photo with them. It may just look like they are happy all of the time, but the smiling is actually an evolutionary feature that helps them to pant and cool off.
The above information was pulled from this site, where more information can be found about these adorable beings.