We have time for a couple more questions. One thing that'd be helpful as if guys could each kind of tell us what you define as parenting. If it's true that what we do as parents makes a huge difference, how do you account for the fact that e siblingsa raised i ame household are as different as siblings raised in different households? You said it's because when we parent even siblings in the same household, we treat the siblings slightly differently. Yes, that's probably true, but we can't possibly treat them as differently as an entirely different set of parents would treat two siblings separated at birth. How do you account to all these twins that have been brought up separately,