I don't think you are a monster. I do think you gave control and power of the situation to your child which is causing you to second guess yourself and your motives for dispatching the rooster. Perhaps since the kids know that it will happen it would be best for them to not know when it is happening? The first one is always the hardest. Once dinner is served and over (don't tell them until after they are eating the rooster) take a few minutes to talk about it. The next one won't be much easier but the kids will come to accept it as part of their life and routine. Extra roosters are for the table and we enjoy them while they are crowing and even more while we are eating.