Laura Linney's and Kathy Bates' character are supposed to be of the same age in the movie while in reality Laura Linney is 16 years younger than Kathy Bates.
Producers Joshua D. Maurer and Alixandre Witlin have been trying to make this project for over 18 years.
The project was originally sold by Maurer to HBO in 2005 with writer James Smallhorne also attached to direct with a cast that included Maggie Smith, Kathy Bates, Joan Allen, Claire Danes and Brenda Blethyn, but the project did not go forward. Maurer and Witlin never gave up hope or faith in the film and continued year after year after year to find the financing to make this movie. After getting constant rejections, Maurer and Witlin finally found interest from Lionsgate UK and Embankment to finance based on an extensive rewrite that Maurer authored in collaboration with Tim Prager, whom Maurer hired. Maurer and Witlin then used this new draft to get commitments from Smith, Bates and Linney. In addition, Maurer and Witlin then hired director Thaddeus O'Sullivan and UK producer Chris Curling and together they brought on and hired Irish producers ShinAwil and BCP. The film was then further delayed due to COVID three more times.
There was some mild criticism in the Irish media that two of the main cast (Maggie Smith & Kathy Bates) who were playing Irish women weren't actually Irish (Smith is English and Bates is American). Laura Linney is also American but her character's accent is explained away in the story.
Kathy Bates (Eileen Dunne) and Stephen Rea (Frank Dunne) were aged 74 & 77 during filming yet were parents to six children who appear to be aged between about 10 and 21. This is actually a holdover from when the producers tried to make the film nearly twenty years ago. When the project finally went into turnaround in 2021 or 2022, rather than recast the parts with younger actors, the producers stuck with the original choice of actors from 2005 but they were heavily made up to make them look much younger than they were.
Dame Maggie Smith's final film released while still alive.