When I was in grade school, it seems everything I did, my mom found out about. At one point I thought Mom might have been some kind of spy or something.
I had good reason to think that. Mom became pretty well known at her office for a particular kind of cake that she made. One summer, she had made that cake, and we had enjoyed it for supper. My brother and I had gone swimming the next afternoon, and when we got home we were hungry. There was one piece of cake left, and I called mom at work and asked it I could have it. Mom told me I could, and I was just about to grab it when my brother saw me. He had his sights set on that cake as well, and we began to argue over the cake.
A few minutes later, Mom came in and told us she knew we were arguing about the cake. I had no idea how she had figured it out, until she told me I had not hung up the phone, and she could hear us from the other end.