Animated characters can grow from a character standpoint without really aging, or even without changing the core character traits. Futurama is a great example. Some of the characters on Futurama followed a cumulative progression -- i.e., things they learned, the ways they grew, and the character relationships they developed were additive, cumulative, and preserved as the show progressed. However, there was very little in the way of an overt passage of time for the characters. Granted, it isn't serious and deep character development, but the development they DID do with the characters was done so in an internally consistent and accumulative manner over time. Throughout Fry's journey, he has learned things and cultivated relationships that were gradually added to his character as the series went on. By the end of the series, Fry still may have been basically the very same Fry with the very same personality traits from episode one -- but he also grew to be more than that.