Nell is a 1994 American drama film, directed by Michael Apted from a screenplay written by William Nicholson. The film stars Jodie Foster (who also produced) in the titular role. Liam Neeson, Natasha Richardson, Richard Libertini, and Nick Searcy are featured in supporting roles. Based on Mark Handley's play Idioglossia, which was inspired by Handley's time living in the Cascade Mountains in the 1970s, and the story of Poto and Cabengo, twins who created their own language, the film's narrative follows a young woman who has to face other people for the first time after being raised by her mother in an isolated cabin. The original musical score is composed by Mark Isham.

Is it true that is movie nell based on a true story?
yes