Wait for response(s) from children.
filter children’s responses, then Send() response
Children Send() response(s).
- N.B. Children operate in any order.
- N.B. Child sequencing determined by Scheduler.
loop for all children collecting responses
filter reponses and Return().
Children invoke Return to send responses.
- N.B. Children operate in the order given by the loop.
- N.B. Child sequencing determined by Parent.