It’s often said that twins share their own language, but for Alison Ross Green and Amanda Ross Bacon, it’s more than that. Their lives are not only intertwined, but have unfolded in a kind of mirrored harmony—they are both involved in creative pursuits, share a taste for the same pleasures and value family deeply. So it’s no wonder that conversations with them are filled with overlapping thoughts and unfinished sentences that the other instinctively completes. “We talk at least five times a day,...