On my phone, I can make different ring tones for different numbers. I have all 800 and 877 numbers set to silent. That keeps me from even knowing when they call until I go through my messages. If he calls again, I would go ahead and change my phone number. How old are your children? Can they change their numbers or do you have to do that for them? In any case, I'd change all numbers so he cannot contact you. If you want the calls to stop, you are going to have to be the one to take care of it.