here I am trying to figure out what to do with my 9 yr old son...

He has been experiencing some severe anxiety the past month or so. I don't suffer from anxiety/depression, but it runs in both my family and my wife's family. He is worrying so much that it is causing him headaches and throwing up. It has been a struggle to keep him in school the whole day, and many times he doesn't want to go to other scheduled events or obligations either. We have recently started having him talk to a therapist, which he admits he likes. However, he won't talk to us about all of his issues. He will mention some of the irrational worries that he has sometimes, but won't talk about anything bigger that might be bothering him.

I'm not really sure what to do here, because I haven't been this close to something like this before. I'm concerned that it will get worse and that I won't be able to help him. I never tell him to stop worrying, or that nothing bad is going to happen. Rather, I just want him to find ways to cope with the anxiety and be able to function. We can't be perpetually picking him up from school early, or leaving church early, or other things like that, because it wears on us, and like I said, I need him to learn to cope and do hard things sometimes.

Anyone else have kids or family with similar issues that can provide some guidance here? TIA.