Photographer documents sisters over 40 years in stunning portraits

While visiting his wife's family in the summer of 1975, photographer Nicholas Nixon was asked by wife Bebe to take a portrait of her and her three sisters. After he saw the black and white image developed of the beautiful, down-to-earth quartet, he asked if he could take a portrait of them every year.

Across nearly his entire professional career of four decades, Nixon documented the Brown sisters, finally unveiling the collection to art exhibits a few years ago. At the time of the first photo, the girls (from left to right) Heather, Mimi, Bebe and Laurie ages ranged from 15 to 25.

Using an eight-by-ten-inch view camera, whose large negatives capture a wealth of detail and a luscious continuity of tone, Nixon and the Brown sisters managed to come together every year for their annual portrait.

In every photo, you won't find the cheerful, made-for-camera smiles, but guarded gazes penetrating the lens. As the girls age into women, little changes about their personalities reflected in the photos. The same amount of closeness, or distance, between each stays relatively the same as much as their facial expressions remain unchanged.

All forty photos are currently on display at the Museum of Modern Art to coincide with the museum's publication of the book, "The Brown Sisters: Forty Years." The museum hopes that Nixon and the Brown sisters will continue the project for many years to come.