This article is from the Dissociation FAQ, by Discord (email@example.com) with numerous contributions by others.
The core personality is often the same as the birth personality, but we
have been informed that this is not necessarily the case. The multiple
who so informed us tells us that in their case, the core was _created_ to
be the holder of the memories and, later, the main adult alter. However,
this is not the same as their birth person.