Kids are tough, man

And I don't mean they can handle themselves in a street fight.
They're just tough to handle. Just when you have your first one figured out and you're counting your blessings that you've given your child a decent head start in life, you realize that your second (or third, or whatever) child is a completely different being, and requires you to start all over again. There is, from what I can see, not a single shared characteristic between our two daughters, aside from the last names. While we have our occasional victories and countless struggles, we're figuring it out little by little. But seriously, where's the road map for this stuff?
Trying to make a very open case in the house that both girls are being treated equally is probably just a few degrees of difficulty down from peace in the middle east. Thank goodness the girls aren't as heavily armed.