Identify child processes from parent process

[Sathwik]

Hi

Given a process instance ID of a given process how is it possible to 
identify child process instances that are created or invoked by the 
parent process.
I suppose it can be identified from the message exchange if the call is 
made through P2P, question is if the call is not through P2P then how do 
we establish this relationship.

regards,
sathwik