You might want to set something up so that each of you has contact with the kids at a certain time of the day, every day. My x calls at 7 each night - I know it is him and don't go near the phone. Who cares if she feels that you are intruding? They are your children, too. Call and ask to speak to them. If she starts a convo, you can say "I can't discuss that right now; I am calling for the kids." Then, be a broken record.
