A neighborhood family is out for an evening stroll. I am behind them and I see that they have arranged themseves in perfect symmetry. The adults walk on either side of the double stroller in which their toddlers sit side by side. The mother is on the right; her left, or inner, hand holds the stoller push bar. Her husband on the left pushes with his right hand. In their free hands both parents hold cell phones to their ears and carry on separate animated conversations.