There are two different universes:
CJ and Sweet were in the 3D universe (GTA III, VC, SA).
Now, a new universe started with GTA IV called the HD universe (GTA IV, GTA V)
In the HD universe none of the events of San Andreas ever actually happened, nor did CJ and Sweet ever exist in it.
Kinda confusing, but it is what it is..
- Get_Head_Ed likes this