Born on 18th April 1946, the daughter of famed actors John Mills and Mary Hayley Bell, she followed in her parents' footsteps and took to the stage at a young age. Her film debut was at the age of eleven in the British crime drama Tiger Bay. It was in that where she was discovered by Walt Disney, who was desperately looking for an actress to play the lead role in Pollyanna. She got the part and, although the film was not a great Box Office success, she was signed to a six film contract with Disney. It was with Uncle Walt that she made another of her most famous films - playing both Susan and Sharon in The Parent Trap.
As is the case with many child actresses, Hayley tried to distance herself from her Disney roots as she got older. Roles such as a mentally-challenged teen in Sky West & Crooked, a virgin trying to consummate her marriage in The Family Way and the object of a stalker's lust in the horror film Twisted Nerve. She dropped out of the industry for a few years, before re-emerging in the 80s, once again working with Disney - filming three sequels to The Parent Trap. She was given a Disney Legends Award in 1998.
She's still acting on the stage to this day. She was also the final recipient of the Academy Juvenile Award in 1960, for her performance in Pollyanna. Her son Crispin Mills is the frontman of Britpop band Kula Shaker.
- Tiger Bay (1959)
- Pollyanna (1960) - Pollyanna Whittier
- The Parent Trap (1961) - Susan Evers/Sharon McKendrick
- The Parent Trap II (1986)
- Parent Trap III (1989)
- Parent Trap: Hawaiian Honeymoon (1989)
- Whistle Down the Wind (1961) - Kathy Bostock
- In Search of the Castaways (1962) - Mary Grant
- Summer Magic (1963) - Nancy Carey
- The Chalk Garden (1964) - Laurel
- That Darn Cat! (1965) - Patti Randall (final film for Disney)
- The Moon Spinners (1965) - Nikky Ferris
- The Truth About Spring (1965) - Spring Tyler
- The Daydreamer (1966) - The Little Mermaid (voice)
- The Family Way (1966) - Jenny Fitton
- Twisted Nerve (1968) - Susan Harper
- Deadly Strangers (1976) - Belle Adams
- Murder, She Wrote (1986) - Cynthia Tate
- Good Morning Miss Bliss (1987-1989) - Miss Carrie Bliss
- A Troll in Central Park (1994) - Hillary (voice)
- Wild At Heart (2007-2012) - Caroline Du Plessis
- Midsomer Murders (2014) - Lizzy Thornfield
Tropes relating to her work:
- Contractual Purity: Her contract with Disney was why she couldn't play the title role in Lolita. She also sought to shake this off by appearing nude from behind in The Family Way and topless in Deadly Strangers.
- Fake American: Half of her roles in America, varying in whether she's bothering with the accent or not.
- Former Child Star: Subverted. For a while she was best known as Pollyanna and Susan & Sharon, but she has kept working in adulthood and carved out a respectable stage career.
- Real-Life Relative: She did The Family Way with her father John Mills.