That depends on how you might assess the capabilities of your child based on age and size! Take into consideration grip and hand-eye coordination. Overall, it would probably be the best start off with an easily loadable water cannon. With that, all your kid has to do is point and push out the water. To refill it, all they have to do is dunk the barrel and pull the plunger up. The second alternative might just be a little clear water pistol with a small trigger and refill nozzle. Either way, invest in something cheap that you don’t mind getting broken right away.