There is something you can use to alert you to an incoming phone call, and then you can decide whether to take it or not, but I can't remember what it's called!!! I'll see if I can ask my friend, Karel, who has it and get back to you. I'm assuming it would be available worldwide, not just in the US.

I know that has to be frustrating. My daughter goes through it at her dad's house and she's only allowed on at 15 minute intervals as a result.