How a 4-year-old brain works

Yesterday Elizabeth didn't take a nap when I put her down after lunch. She does this every once in a while. I guess it has been happening with an ever increasing tendency. So, later in the afternoon we did a little shopping at Walmart for a few things. On the way home, Elizabeth will often fall asleep in the car and take just enough nap to make it until bedtime. And we were hoping for this. However, Emma was on a roll and was talking and talking and talking. We tried to ask her to keep her voice down, maybe listen to the wind, please be quiet for your sister, etc. etc. It was not working. Finally I blurted, "Just be quiet!!" And Emma jumped to the logical conclusion of, "You don't like my voice??!?!?!" and proceeded to burst into tears. This was obviously not working. How can I reason with that kind of logic? I back-tracked with, "no, no, I love your voice, we just need quiet so Elizabeth can sleep." But it just didn't pacify her. Howling, moaning, whining; and that doesn't even describe Elizabeth at this point. So we got home and unloaded all us grumpy folk, and settled in for a long evening. But I will say that I do love 7:30 bedtimes.