Hi AC,
yes, both are owned by Freescale (KDS is produced by an external vendor).
Processor Expert is a technology/tool which allows you to graphically configure your device and software, generate source code and then use it for your application.
Processor Expert exists either standalone (within Eclipse) so can use it with your own tool chain, or IAR, or Keil, etc.
That technology comes pre-integrated with IDE's too, like in CodeWarrior or Kinetis Design Studio.
So from the technology it is the same: the difference is how it is packaged or which build tool chain/compiler/etc is used.
Erich