Suggestion that has worked for me in this same case when my son was young: Have the boy play two or three "simple" PCs and you play one NPC or two.. possibly even his "pack bearers" or pages who are actually full PC possibly even more capable in key areas. This allows a full group of four. He plays the fighter and the cleric and the Page is a wizard while the alcot to the cleric is a thief... all on the QT mind you... anyway, was a good way to do any adventure with full group AND keeps things going if the "one PC" goes down...
Wow, Another Natural One! You guys are a sink hole for luck. Stay away from my dice.