Who's Still Around The Morning After?

Why is it that the morning-after fatigue is so much worse when the night-before was spent wrestling a three-year-old to sleep rather than sitting in a smoky bar with 100 decibels aimed at my head? I guess perhaps it's because I'm not waking up with any fun memories of revelry, just a fuzzy recollection of tiny toes digging into my stomach while I traversed the Parenting Tactics spectrum between "Honey, hush," and "Shut it!" Or maybe because, when one of my friends starts whining "I'm hunnnngryyyy" at 2:00 in the morning, the next logical step is a trip to IHOP, not a thirty minute discussion about why we can't eat applesauce in bed.