For many reasons, but lately, because she is my daughter who doesn't find that it's necessary to talk (or yell) every waking minute of every day.
Erin asks lots of really hard to answer bizarro questions. Example from this evening, "Mama, what do you do if an animal that is trying to eat you has you in his mouth?"
And in addition to solving such life and death dilemmas and fielding her rapid-fire quizzes, such as why cooking makes things hot or why bread tastes like bread, I have to acknowledge every minute observation of hers, which occur constantly:
"Mama, that man has a very brown shirt."
After which I have 3.2 seconds to answer with a "yes, Erin" or else I'll hear:
"MAMA! THAT MAN HAS A VEEEEEEEEERY BROOOOOOOWN SHIRT, I SAID!!!"
Kate is just an uncaged parakeet, chatting constantly about everything, or maybe a lot of the same things over and over. It can be hard to tell, but rest assured, if Kate is awake, she is talking.
Allison can speak just as well as Kate can but for some reason she doesn't feel the need to prove it constantly. Thank goodness for that.