A little boy kissing an orphaned kangaroo joey at a kangaroo orphanage in Australia. It's unfortunate that I can't find the name of the actual photographer that took this shot? I liked the image so much that I had to post it on my blog!
Marsupials have an extremely short gestation period (about 4-5 weeks), and the joey is 'born' basically in a fetal state. The blind, furless, miniature newborn, the size of a jelly bean, crawls across its mother's fur to make its way into the pouch, where it latches onto a teat for food. It will not re-emerge for several months, during which time it develops fully. After this period, the joey begins to spend increasing lengths of time out of the pouch, grazing and learning survival skills. However, it returns to the pouch to sleep, and if danger threatens it will seek refuge in its mother's pouch for safety.
Joey's stay in the pouch for up to a year in some species, or until the next joey is born. A marsupial joey is unable to regulate its own body temperature, and thus relies upon an external heat source. Until the joey is well furred and old enough to leave the pouch, a pouch temperature between 30-32 degrees in Celsius must be constantly maintained.