Back in 1975, photographer Nicholas Nixon snapped a photograph of his wife and her three sisters. A year later, an opportunity presented itself for him to line them up in the same way and snap another—an event that has since gone on annually for the past 40 years. The New York Times recently revealed the latest in the series, and all of the photos will be on display at NYC’s Museum of Modern Art next month. The humbling collection captures an unwavering timeless gaze from all four sisters that projects intimacy while keeping their privacy. The engaging images are a must-see in person.