When two brothers approached Mexican architect Alonso de Garay about designing a weekend family compound, they told him they wanted identical side-by-side houses. The site, on a steep hill, overlooks Lake Valle de Bravo, a two-hour drive south of Mexico City. For each house, they specified a generous foyer, two kitchens (one open and one for service), a living room, dining room, gym, five bedrooms, a family room, covered terrace and 25-meter lap pool. In addition, they needed a common area (each brother has four children) where the families could get together.