Conversation so far:
What was the four year old season for the race horse affirmed?
What was the public reception about race horse Affirmed?
Who was race horse Affirmed's rider?
Steve Cauthen was Affirmed's regular rider.
Did Steve Cauthen and Affirmed have a good relationship?

Question: How long did they work together?
Self-contained rewrite: How long did Steve Cauthen and Affirmed work together?