PhysX Bind - but not between elements

[CLF73]

Few ways...
Here's one...
Add custom property above voronoi, with float Birth ID.
Then in the PhysX Bind, turn on clustering with that float value.

Attaching you quick example file... turn on and off clustering in the PhysX Bind, and you will see that it works.

Makes sense. 
Thank you for your reply.