Louise told stories to Jacqueline and Jillian, told them they were clever, they were strong, they were miracles. She told them to sleep well and dry their eyes, and as they grew older, she told them to eat their vegetables and pick up their rooms, and always, always, she told them that she loved them. She told them that they were perfect exactly as they were, and that they would never need to change for anyone. She told them that they were going to change the world.

Gradually, Chester and Serena learned to tell their own daughters apart. Jacqueline had been the first born, and that seemed to have taken up all of her bravery; she was the more delicate of the two, hanging back and allowing her sister to go ahead of her. She was the first to learn to be afraid of the dark and start demanding a nightlight. She was the last to be weaned off the bottle, and she continued sucking her thumb long after Jillian had stopped.

Jillian, on the other hand, seemed to have been born with a deficit of common sense. There was no risk she wouldn’t throw herself bodily against, from the stairs to the stove to the basement door. She had started walking with the abruptness of some children, going through none of the warning stages, and Louise had spent an afternoon chasing her around the house, padding the corners of the furniture, while Jacqueline had been lying comfortably in a sunbeam, oblivious to the danger her sister was courting.

(Serena and Chester had been furious when they came home from their daily distractions to find that all of their elegant, carefully chosen furniture now bore soft, spongy corners. It had taken Louise asking how many eyes they would like their daughters to have between them to convince them they should allow the childproofing to remain in place, at least for the time being.)

Unfortunately, with recognition came relegation. Identical twins were unsettling to much of the population: dressing them in matching outfits and treating them as one interchangeable being might seem appealing while they were young enough, but as they aged, they would start to unnerve people. Girls, especially, were subject to being viewed as alien or wrong when they seemed too alike. Blame science fiction, blame John Wyndham and Stephen King and Ira Levin. The fact remained that they needed to distinguish their daughters.