Ndume's sister, Ibu, gave birth to a female infant on September 13, 1997, at the Pittsburg Zoo.

Gorilla moms keep their babies close by for the first three months and nurse them for about the first two years.

Once they're a little older, the kids wrestle, slide down tree trunks, chase each other, dress up in leafy branches and play "King of the Hill" and "Follow the Leader." They even play ball games with pieces of round fruit.