Surprisingly, there is no biography (official or unofficial) of Mills, and very little in the way of memoir or autobiography. I have gleaned information from various popular magazine stories available online, as well as a variety of more-and-less reputable sources, including:
Internet Movie Database:
http://www.imdb.com/name/nm0001539/bio
Wikipedia:
https://en.wikipedia.org/wiki/Hayley_Mills
Reel Classics:
http://www.reelclassics.com/Actresses/Hayley/hayley.htm
People Magazine: ‘Pollyanna at 50’, 1997:
http://people.com/archive/pollyanna-at-50-vol-47-no-13/
Huffington Post: ‘First choice for Lolita, Hayley Mills, attends rare screening of Whistle Down the Wind in Hollywood’, 2011:
https://www.huffingtonpost.com/penelope-andrew/hayley-mills_b_881441.html
Senior City: ‘Celebrating seniors: Hayley Mills turns 70’, 2016:
https://seniorcitylocal.com/celebrating-seniors-hayley-mills-turns-70/
I have also quoted from a short interview with Mills in Brian McFarlane’s An Autobiography of British Cinema (London, Methuen, 1997); and consulted various TV and radio interviews to be found on YouTube, although these are mostly less than illuminating. The exception to this is the British TV interview with Mills, conducted in 1967, available online from the British Film Institute: https://player.bfi.org.uk/free/film/watch-hayley-mills-1967-online.
On child stardom, my main source here has been Gaylyn Studlar’s book Precocious Charms: Stars Performing Girlhood in Classical Hollywood Cinema (Berkeley, CA: University of California Press, 2013).
There is a vast literature on Disney, although very little of it focuses on the studio’s live action films. I reviewed some of this many years ago in an article for Media, Culture and Society, ‘Dissin’ Disney: critical perspectives on children’s media culture’: http://journals.sagepub.com/doi/abs/10.1177/016344397019002010. My study of British parents’ views of Disney is contained in the book Dazzled by Disney? The Global Disney Audiences Project edited by Janet Wasko, Mark Phillips and Eileen Meehan (London: Leicester University Press, 2001).
I have made some use here of Richard Schickel’s The Disney Version: The Life, Times, Art, and Commerce of Walt Disney (3rd edition, Chicago: Ivan R. Dee, 1997: first published 1968) and Steven Watts’s The Magic Kingdom: Walt Disney and the American Way of Life (Columbia, MI: University of Missouri Press, 1997). Specifically relating to the issue of childhood, I have particularly drawn on Nicholas Sammond’s Babes in Tomorrowland: Walt Disney and the Making of the American Child (Durham, NC: Duke University Press, 2005). Frances Clarke Sayers’ essay ‘Disney Accused: Interview with Charles M. Weisenberg’ (1965) was published in the Horn Book Magazine 41: 602-11. Douglas Brode’s rather idiosyncratic view of Disney can be found in From Walt to Woodstock: How Disney Created the Counterculture (Austin, University of Texas Press, 2004).
Several of the Disney DVDs of Mills’s films contain ‘making of’ documentaries, all predictably glowing with praise and lacking in information.
Critical analyses of specific films
The book Walt Disney, from Reader to Storyteller, edited by Kathy Merlock Jackson and Mark I. West (Jefferson, NC: McFarland, 2015) is also rather dominated by adoration for Disney, but it contains some useful essays on these films:
Judy Rosenbaum, ‘Adapting Pollyanna for the space age’;
Susan Larkin, ‘The sentimental novel: community, power and femininity’ [on Pollyanna and Summer Magic]; and
Ron dePeter, ‘Hayley Mills and the constraints of artifice in That Darn Cat!’
In order of appearance, I also refer to:
Chibnall, Steve (2000) J. Lee Thompson (Manchester: Manchester University Press, 2000) [section on Tiger Bay]
Williams, Melanie (2005) ‘”I’m not a lady!” Tiger Bay (1959) and transitional girlhood in British cinema on the cusp of the 1960s’, Screen 46(3): 361-372
Brewer, Sandy (2000) ‘”Who do you say I am?’ Jesus, gender and the (working-class) family romance’, in Sally Munt (ed.) Cultural Studies and the Working Class (London: Bloomsbury) [background on Whistle Down the Wind]
Dux, Sally (2012) ‘Allied Film Makers: crime, comedy and social concern’, Journal of British Cinema and Television 9(2): 198-213 [context for Whistle Down the Wind]
McReynolds, William (1974) ‘Disney plays “the glad game”’, Journal of Popular Culture 7(4): 787-796 [on Pollyanna]
David Buckingham 