Vervets are Old World monkeys. They are common and said to be aggressive, but this most likely depends on the situation they are in. Most animals are aggressive in defense. Vervets are very smart and like other monkeys, can learn new habits in a 24 hour period.

"Infants spend the first week of life clinging to their mother's stomach. After about the third week, they begin to move about by themselves and attempt to play with other young monkeys. Infants are of great interest to the other monkeys in the troop; subadult females do everything possible to be allowed to groom or hold a new infant. Researchers report that usually a female's close family members will have the most unrestricted access to the babies. As the infants grow, they play not only with monkeys but also with other young animals." --Awf.org

-Keep wild animals wild-