A kangaroo is only truly pregnant for around 1 month, but she carries her baby kangaroos in her pouch from 4 months to sometimes more than 1 year. The length of time in the pouch depends on the specific type of kangaroo.
Kangaroos belong to a class of animals called marsupials. The one major identifying trait of this infraclass is the pouch that babies are carried around in after birth. These animals give birth to live babies that are not able to survive on their own. These babies crawl into the marsupial pouch after they are born and nurse to continue to receive nutrition from their mothers. They do not leave the pouch until they have grown enough to be able to survive without their mother's milk.
A group of kangaroos is called a mob, a female is called a jill, a male is called a jack and a baby is called a joey. Kangaroos most commonly live in mobs that have one or more family aspects to them. They are colonized animals and work together to hunt, graze and protect their young. They primarily hunt grass, shrubbery and berries because they are herbivores. Kangaroos can be found in a variety of locations that have greenery for them to eat, and they are able to adapt to nearly any type of living situation or environment.