The Walters family has two sons, aged four and seven. These sweet boys look so much alike that I do a double take each time I see them. Their mom dresses them in matching outfits for holiday photos, and their parents hear a constant litany of how much they resemble each other. But appearance is where the resemblance ends. Having gotten to know these two children, I can tell you that their personalities are nothing alike. Geoff, the elder, is quiet and studious. He’s a rule follower and a bit of a worrier. While he can laugh at a good joke, his outlook is generally serious and even contemplative. Younger brother Ethan, on the other hand, is all fun, all the time. This free spirit lives for the moment, never worrying about what’s coming next. Less interested in early academics, he shines socially. He keeps his family and friends in stitches with his hilarious antics. These parents scratch their heads at the obvious difference between their two boys, and wonder how two young children