Quote: "He has `G` down perfect but can`t seem to get the low `C` -- ok they`re both open fingering... how do you do this??"

There was a kid in our band that had the same problem. Is your son set on playing trumpet? Because the kid switched to Eb baritone horn and played it like a charm!!

That music teacher is being a jerk. Tell him to stop pressuring your son because any good player needs time to learn.

The best thing to do about the lips is to just keep on buzzing the mouth piece, and to practise buzzing without it, it is still early days, eventually, his lipps will relax into buzzing