Sloths are divided into two large groups: Bradypus, the three-fingered sloths that include the famous smiley and masked-face sloths, and Choloepus, the brownish ones with a pig-like nose and two fingers on each hand.

These two sloths are not only different species, but they belong to two completely different families, separated by over 30 million years of evolution. Cross-species adoptions like this are incredibly rare in the wild, with only 3 other documented observations of this happening.