In the original novel by Frances Hodgson Burnett, Mary's father and Colin's mother were brother and sister. The revision of having Mary's and Colin's mothers' identical twins and Mary's resemblance to her mother, therefore reminding Archie Craven of his late wife, was first seen in The Secret Garden (1993) and repeated with this film.
Released two years after being filmed.
The Secret Garden's release date was been postponed due to the COVID-19 pandemic. It was eventually released digitally on September 22, 2020, and on Blu-ray and DVD on October 6, 2020.
Mrs Medlock is played by Julie Walters in this film and Maggie Smith in the 1993 version. Both actresses are in the Harry Potter series.
In addition to starring in Mamma Mia! together, both Colin Firth and Julie Waters starred in Mary Poppins Returns