One lead, at thirteen, in which the best thing in the film was her lying in a bed and being looked at; one franchise part that asked only for screams. On the evidence of The Wonder, she is an actor who rewards being watched.
Fi1m perspective
For most of The Wonder (2022) Anna O'Donnell lies in a bed in the Irish Midlands in 1862, says she has not eaten in four months, and is looked at. Kíla Lord Cassidy, thirteen when she played her, does the thing child actors are almost never allowed to do, which is almost nothing. She recites her prayers as if they were a comfort nobody else in the house has, folds her hands, and gives no sign of whether she is a saint, a fraud or something sadder. Florence Pugh's nurse watches her for evidence. So did we.
She had worked before: a feature debut at nine in The Doorman (2020), a television miniseries, Viewpoint (2021). But The Wonder is the part, and it is the one to click through to. Sebastián Lelio surrounds the girl with adults who each want her to be something, and Cassidy has to be the surface they write on without going blank herself. Her mother, Rosaleen, is played by her actual mother, Elaine Cassidy, and the two of them share a shorthand no rehearsal buys: the mother's kiss looks like one that has happened a thousand times. We found her uncanny without seeming to try.
The second half asks something harder of her, in scenes we will not describe, and it frightened us. Cassidy plays a child in trouble without once reaching for our sympathy, which is exactly why we gave it. It is the best thing in a film that otherwise wobbles, wrapped in a framing device we could have done without and giving away in its last half hour much of what the first had built. None of that is hers to answer for.
The Conjuring: Last Rites (2025) gave her Heather Smurl and then forgot her. The script decides the Warren family is the subject and the Smurls are a case file, and the four girls, Cassidy among them, are a set of reactions rather than people. She screams when the house wants a scream and looks pale when it wants pallor, and does both competently. Nobody could have made Heather a person from those pages. It tells us only that a franchise will hire her, not what it would take to use her.
Two more girls follow, Molly in the boxing drama Salvable (2025) and Fanny Savage in Savage House (2026), alongside Claire Foy and Richard E. Grant, back in period dress. The parts so far are children who are observed or left alone, and she is good at being watched. She called her casting in The Wonder "like winning the lottery". It was, for Lelio as much as for her. The thing to watch with the next director is whether they look at her or past her.
Biography
Kíla Lord Cassidy is a British actress. She was born on 16 September 2009 in London.
She made her feature film debut in The Doorman (2020). Her breakthrough came with the role of Anna O'Donnell in The Wonder (2022), for which she received a nomination for Breakthrough Performance at the British Independent Film Awards. She has also appeared in the television miniseries Viewpoint (2021) and films including Salvable (2025) and The Conjuring: Last Rites (2025), in which she plays Heather Smurl.
She is the daughter of actors Elaine Cassidy and Stephen Lord.
