In 1965, aged two, Williams was assessed as "psychotic". During the rest of her childhood, she was tested multiple times for deafness and labelled as "disturbed". In 1991, she was diagnosed as autistic and also underwent treatment for gut, immune system and sensory perceptual disorders. She wrote four autobiographies – "Nobody Nowhere: The Extraordinary Autobiography of an Autistic Girl" (1992), "Somebody Somewhere: Breaking Free from the World of Autism" (1994), "Like Colour to the Blind: Soul Searching and Soul Finding" (1998) and "Everyday Heaven: Journeys Beyond the Stereotypes of Autism" (2004) – and released two albums, "Nobody Nowhere" and "Mutation". During the mid-1990s, she was the subject of several TV documentaries.