I have two Hoyt Banchees for my two boys. One is 20 lbs. the other is 40 lbs. I will say 40 lbs. zips a arrow pretty quick. Its kind of the border though on being enough to take down a deer. It is a 40 lb law here in Ohio. I would not think anything less would be good for a clean kill. Plus you would not want to discourage a young hunter with wounded deer. Its great to hear you will have a little hunting partner for years to come.