Agree with Fadered and others
Mom made me buy a 30" boat for our 6 year old for “safety” reasons. One weekend of bruised knuckles and I got the green light for the 21" model I wanted all along. Paired with a good kids paddle like the Werner Sprite or Little Dipper (small shaft) makes ALL the difference in the world. Barked knuckles will turn a kid off to paddling before they discover the good stuff. The right gears goes a long way in the long run. Pay your dues now 'cause who else is going to be paddling with you when your 80?