After Maria changed Jasper, she went on to create an army of newborns. One of those newborns was Charlotte. Jasper and Peter were set to destroy her, along with the other newborns who were outgrowing their strength, but when her turn came, Peter "yelled for [Charlotte] to run, and he bolted after her (Eclipse, pg. 299). She returned with Peter sometime later and Jasper travelled with them for several years.
In Breaking Dawn, Charlotte and Peter witness in defense of Renesmee when the Volturi arrive.
