The Red Kangaroo is the largest living marsupial. Adult males often fight each other in the breeding season, boxing with their front paws and kicking with their back legs. Females are sexually mature at about 18 months, males at about two years. A single joey is born at a time. The joey remains in the pouch for five to six months. The joey gradually spends time away from the pouch. Joeys are usually weaned at about one. Females can have three young with her at the same time - one as an embryo, one in the pouch and another out of the pouch still suckling.