Herseth's Vote Against Parental Notification

The House once again passed a bill making it a federal crime to transport a minor across state borders to obtain an abortion and in order to avoid state parental notification laws.  One would think that parental rights would extend far enough to give parents the right to know if their daughter is getting an abortion or not.  Forty Democrats agree with that proposition (see the roll call here).  Apparently Stephanie Herseth does not, as she voted against this very modest bill.  Is there any wonder why there is such a big marriage gap?