The Solarium was always the brightest room. It was built with enormous, reinforced glass panels that let the sun stream in, turning the plush, pale carpet into a giant, warm play mat. For the past hour, the space had been dedicated entirely to the serious, demanding business of infancy.

Ivan and Giovanni were engaged in a low-speed, highly focused crawl race toward a collection of soft, non-lethal blocks. Mamma, Chiara, was sitting with me on the floor, gently supervising while attempting to ...