i understood what you meant..not new as in newly created, new as in new compared to ones you have already known about. the same happened to me this last year or so where new ones were discovered...though i have a feeling they were known about but not fully to me which is confusing because when i did become more aware of them, it was like i already knew about them.

also, alters are not 'only' created by a trauma; they can be created for any number of reasons once you already have developed DID.

i don't know what age mine started developing, i'd say between 4/5 and 10 or so. the reason i say that is because they SAY that in children, they start becoming more self aware/world/reality aware and tend to lose the imagination aspect around age 10/11 or so...but i didn't appear to (also cuz of the dissociation), so i may have been developed others even after the age of 10 or so when other difficult things came up (not necessarily traumas, though i did have some occur in my teen and early 20s).

it takes a long time for me to get to know the others since my system seems to change..though that's also meaning some are more active or more quiet...so i don't have a lot of access/communication to learn about them more.