You are quite welcome for the info!
A seven yr old can learn barrels. Freshen up on your handle and response. Work on some horsemanship patterns.
Then once you have good response and focus, start doing slow work excercises. Email
MrsTinaSpangler@aol.com and see if she can hook you up with patterns and excersices.
Figure 4 to 6 months of foundation work before slow working the cloverleaf.
You could get him to do it quicker by skipping steps, but he probably won't be as solid.
Look at it as a challenge.
Have fun with it!