Poto and Cabengo

Poto and Cabengo (names given, respectively, by Grace and Virginia Kennedy to themselves) are American identical twins who used an invented language until the age of about eight. Poto and Cabengo is also the name of a documentary film about the girls made by Jean-Pierre Gorin and released in 1980. The film Nell, based on the play Idioglossia, was partly inspired by the twins.

The girls were apparently of normal intelligence. They developed their own communication as they had little exposure to spoken language in their early years. Poto and Cabengo were the names they called each other.

Grace and Virginia were born in 1970 in Columbus, Georgia. Their birth was normal, and they were able to lift their heads and make eye contact with their parents within hours after birth. But both soon suffered apparent seizures, and their father maintained that a surgeon told him the girls might experience developmental disabilities. Misunderstanding speculation for diagnosis, the girls' parents ceased to pay more attention to them than necessary.

Both parents were employed (although later characterized by The San Diego Tribune as living on "food stamps and welfare") and spent many hours away from home. The girls were left in the care of a grandmother who met their physical needs but did not play or interact with them. The grandmother spoke only German, while the parents spoke English. They had no contact with other children, seldom played outdoors, and were not sent to school.

Their father later stated in interviews that he realized the girls had invented a language of their own; but, since their use of English remained extremely rudimentary, he had decided that they were, as the doctor suggested, developmentally challenged and that it would do no good to send them to school. When he lost his job, he told a caseworker at the unemployment office about his family; and the caseworker advised him to put the girls in speech therapy. At the Children's Hospital of San Diego, in California, speech therapists Ann Koeneke and Alexa Kratze quickly discovered that Virginia and Grace, far from being mentally impaired, had at least normal intelligence and had invented a complex idioglossia.

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