Manhattan may not be the first place you would look for a strong family with a good father, but the author of a new children’s book reveals one living on a lake in Central Park. In “The Handsome Little Cygnet,” writer and illustrator duo Matthew Mehan and John Folley show us a family of swans coping beautifully with an identity crisis—in lightly metered prose and 20 gorgeous watercolors. Below, Carolyn Moynihan asks Mehan, a Washington dad, founding contributor to MercatorNet, liberal arts teacher for 20 years, and now a professor of government at Hillsdale College, about his second venture into children’s literature. Carolyn Moynihan: It has been three years since you and John Folley produced your first children’s book, “Mr. Mehan’s Mildly Amusing Mythical Mammals.” How is that one doing out in the world? Matthew Mehan: It’s doing very well. Considering it was our first book and that we didn’t know what …