How long does a baby koala bear stay with mother when born?

Koalas give birth to a single joey after a gestation period of 35 days. The newborn joey is very small, weighing only about 0.5 grams (0.018 oz) and is 15–18 mm (0.59–0.71 in) long. It is blind, hairless, and underdeveloped. The joey remains in the mother's pouch for about 6 months, where it suckles on her milk and begins to develop. After 6 months, the joey emerges from the pouch and rides on its mother's back, suckling occasionally until it is about 12 months old. At one year old, the joey becomes fully independent.