"Scientist Parents' Extraordinary Adoption of Chimpanzee as Baby's Sister Ends Bitterly"

In 1931, psychologist parents Winthrop and Luella Kellogg attempted to raise their son alongside a chimpanzee named Gua in a nature versus nurture experiment, but abandoned it after nine months due to chilling changes in their son's behavior. The experiment involved cruel tests and attempts to teach Gua human behaviors, but ultimately failed to humanize her. The study concluded that there are limits to the humanization of non-human species. Tragically, their son Donald later took his own life at the age of 43, and Gua died in captivity after contracting pneumonia.