In the 1960s, a controversial psychological experiment secretly separated identical twins (and triplets) at birth and placed them into families of different socioeconomic backgrounds — rich, middle-class, and poor — without telling the adoptive parents. The study was led by Dr. Peter Neubauer and backed by the Louise Wise adoption agency in New York.
The goal was to study nature vs. nurture, tracking how environment affected development. Researchers visited the children under false pretenses for years, filming and evaluating them without revealing the real purpose.
The results were never fully published, and much of the data remains sealed until 2066. The truth only came to light when some of the separated siblings accidentally discovered each other as adults most famously in the documentary Three Identical Strangers.