Toddlers are bipolar

So exactly one minute ago Emelia was on the floor crying because, well, I have no idea why, but I am sure it has something to do with what I did or did not do. Now she is happily putting balls back in to the ballpopper. I did nothing in between. I decided that she was clean, safe and well fed therefore I was going to ignore the tantrum. I am not sure if it was the right thing to do but I did it anyway. Note to self, find a book that deals with toddler behavior. Oh my, let's see what else today brings...