What a smile!!!
This past winter I also made a "kid\small frame" size flintlock rifle. 30" 45-cal barrel. I "stole" structure from half-stock's, Hawken hook-breech, Hawken wedge keys (Ease of cleaning), Northwest Trade architecture\trigger guard.
It shoots well, is light, and a kid can handle it much easier than a full length. Lots of work went into it and it's built for a specific purpose of kid friendly. I got some odd responses to the build. Don't let that matter. What's important is to get the kid interested. Everything else is secondary.