He can play with it as long as the parental controls are on. I would probably say the best place to put the pump to start is in the abdomen. You can clip the pump to his pants or leave it right on the side of him. Unless he turns around a lot.
There are some websites that sell sleep clothes for kids with pump pockets in the shirt or pants I recommend Pump Wear Inc they have a huge selection of all different items you can choose from. Not only clothes either, they have really cute kid pump paks.
hope this helps.
It gets frustrating sometimes but stick with it, my son's A1C was 6.1 his last 3 month follow up and 6.0 before that. He was at 8.1 before the pump. I would definetly suggest a soft belt and dual sided zipper pump pack from Pump Wear inc. They will show you different sites for placement, just be sure to rotate the site. He will do fine.