Given that it takes about an hour to get ready to go out for a walk—what with the getting dressed and fed, sock-and-shoed, sweatered, diaper changed or otherwise relieved, not to mention the locating of baby sling and keys, and the negotiating of a peace treaty outlining who gets to open the front door and who gets to open the screen door—given all that, there ought to be a rule that no one will need a diaper change before you get around the block. Scratch that, make it a diaper and complete clothing change. Forty-eight seconds after leaving the house. THERE OUGHT TO BE A RULE.