Because I said so.
But mommy, that’s not a why (answer in four year old speech).
Yes it is, you just don’t like it.
Ouch, right? How many times have we heard that in our lives. >.< I like to pretend I don't have the answer when I don't have an answer I like... but as much as I avoid it, it doesn't make it any easier to deal with or accept. Just gotta eat the frog...