Gestation takes roughly 11 to 13 days to complete, and each litter can contain up to 20 infants, called joeys, which are generally born between February and June.

Joey opossums are small, about the size of a common honeybee, which is why they have quite ahigh mortality rate compared to other animals. But opossums are unique as being the only mammal in the United States or Canada that raise their young in a pouch, just like a kangaroo or koala would. Joeys will immediately go for the mother’s pouch once born, with only around 13 at most surviving the difficult journey.

After around two and a half months, the joeys will have become too large for the pouch. The rest of their growth takes place on their mother’s back, with development from birth taking around 100 days until they become independent.