The child was 3, maybe 4, and walking hand in hand with his mother down Charles Street on a beautiful August day. Boston Common was to his left, the Public Garden to his right, The Four Seasons Hotel ahead and the State House behind. The sky was blue, the sun bright and every tree in the city was in bloom. The people were in bloom, too, little kids, big kids, tourists and natives, colorful in their shorts and baseball hats, suits and sundresses. The streets teemed with cars and trucks, bikes and bikers, busses and trolleys and in the distance, there were even more buildings and people and things. It was a page right out of "Where's Waldo."