ohhhh. I don't know what to say to help you, I think you have been very honest about your feelings in this post, I do admire you for that. I guess you know that 1 in 10 kids still wet the bed at this age, that doesn't help much though.

Is it possible to get his mother to go with all of you to the GP?

It is no solution, but he is 10 a may just grow out of it, as he gets a bit bigger he may really realise that it is socially not acceptable and be ready to change then.

Sorry that isn't much help is it? His mother sounds like she isn't really much help

Good luck.