RE: New release for 9yr old ...
Good training is to have him put his finger behind the trigger and use that finger to push forward on the trigger as he draws. That'd give him a little more confidence. He's doing something to reduce the potential of the releaseaccidently goingoff while he's pulling.
Another thing, if possible, would be to adjust the length of the release so the trigger fits into the middle knuckle of his finger instead of the first knuckle. There's a lot less finger movement there, so the light pull won't be nearly as noticeable.