It is a question with which, I am so conflicted. I so love that my children are curious but really, really, does it have to be asked quite so often? After I just blurted out "because I said so" to my son, a phrase I swore in my pre-parenthood days I'd never say (like I said I was never getting a minivan), I had to remind myself that I am happy they feel so comfortable to ask "why?" so often. I am hoping I will feel better about them asking "why?" when they have used this tool to understand complex chemistry in about 10 years.