# Katherine Mallen Kupferer
**Katherine Mallen Kupferer** (born 2007) is an American actress from Chicago, Illinois, known for playing Gretchen Potter in *Are You There God? It's Me, Margaret.* (2023), Daisy in *[Ghostlight](https://www.edgepedia.org/ghostlight-2024-film)* (2024), and Minnie Dunn in *[Mouse](https://www.edgepedia.org/mouse-2026-film)* (2026). She is the daughter of Chicago stage actors Keith Kupferer and Tara Mallen, and she has worked in professional theater and film since early childhood.[1](https://www.tvinsider.com/people/katherine-mallen-kupferer/) • [2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/)
| Key fact | Detail |
|---|---|
| Born | 2007, Chicago, Illinois[1](https://www.tvinsider.com/people/katherine-mallen-kupferer/) |
| Parents | Actors Keith Kupferer and Tara Mallen; the three played an on-screen family in *Ghostlight*[2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/) |
| Stage debut | Balloon Girl in Chicago Shakespeare Theater's *Gypsy*, directed by Gary Griffin[3](https://www.katherinekupferer.com/uploads/9/5/0/1/95012444/katherine_mallen_kupferer_resume_7_21.pdf) |
| Film debut | Gun Daughter in Steve McQueen's *Widows* (2018)[4](https://www.imdb.com/name/nm10102806/) |
| Breakout roles | Gretchen Potter in *Are You There God? It's Me, Margaret.* (2023); Daisy in *Ghostlight* (2024)[4](https://www.imdb.com/name/nm10102806/) |
| 2026 lead | Minnie Dunn in Kelly O'Sullivan and Alex Thompson's *Mouse*, which premiered at the Berlin International Film Festival[5](https://awardswatch.com/mouse-review-sophie-okonedo-and-katherine-mallen-kupferer-shine-in-tender-portrait-of-grief-and-growing-up-b-berlinale/) |
| Outside acting | Equestrian competing at novice-level horse trials; owner of a Quarter Horse-Thoroughbred cross named Piper[6](https://gigmarketing.us/katherine-mallen-kupferer.html) |
## Family and early life
Kupferer grew up inside the Chicago theater community. Her mother, Tara Mallen, is an actor and the artistic director of Chicago's Rivendell Theatre Ensemble; her father, Keith Kupferer, is a veteran of Chicago stages whose film credits include *The Dark Knight* (2008), *Road to Perdition* (2002), and *Widows* (2018).[2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/) • [7](https://www.betaseries.com/en/person/185489-keith-kupferer) Mallen has said she went into labor at the theater and brought [Katherine](https://www.edgepedia.org/katherine) back there soon after, and that Katherine began writing her own plays and recruiting friends to perform them as a small child.[8](https://www.kosu.org/arts-culture/2024-06-16/in-ghostlight-a-real-life-family-plays-their-reel-selves)
In a 2023 interview, Kupferer said she had been working in professional productions since she was about seven and joined the [Screen Actors Guild](https://www.edgepedia.org/screen-actors-guild) a couple of years before that interview.[6](https://gigmarketing.us/katherine-mallen-kupferer.html) Her parents describe having been cautious about pushing her into the profession; her father said the family never pushed her toward acting, "in fact, a little bit of the opposite," while leaving the decision to continue with her.[2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/)
## Stage work
Her professional stage debut came as the Balloon Girl in Chicago Shakespeare Theater's acclaimed production of *Gypsy*, directed by Gary Griffin; she has said she got the role because her father had been cast in the production and the company was looking for a girl to play the part.[3](https://www.katherinekupferer.com/uploads/9/5/0/1/95012444/katherine_mallen_kupferer_resume_7_21.pdf) • [6](https://gigmarketing.us/katherine-mallen-kupferer.html) Her resume also lists ensemble and child roles in *Killing Game* at A Red Orchid Theatre, *Visions Vast and Small* at Playwright's Realm, and *Big Kids* at Story Theatre.[3](https://www.katherinekupferer.com/uploads/9/5/0/1/95012444/katherine_mallen_kupferer_resume_7_21.pdf) She has said that theater interests her as much as film going forward.[2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/)
## Film career
**Early screen roles.** Kupferer's major motion picture debut was a small part as the "Gun Daughter" in [Steve McQueen](https://www.edgepedia.org/steve-mcqueen)'s heist drama *Widows* (2018), followed by a supporting role in *Fools* (2016).[4](https://www.imdb.com/name/nm10102806/) • [3](https://www.katherinekupferer.com/uploads/9/5/0/1/95012444/katherine_mallen_kupferer_resume_7_21.pdf) Her first substantial film role was Gretchen Potter, one of Margaret's best friends, in Kelly Fremon Craig's adaptation of [Judy Blume](https://www.edgepedia.org/judy-blume)'s *Are You There God? It's Me, Margaret.* for Lionsgate (2023). She has said the film was the first time she spent a long period on a set, and that director Kelly Fremon Craig pushed the young cast to make their own choices and let their personalities come through in their characters.[6](https://gigmarketing.us/katherine-mallen-kupferer.html) • [2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/)
**Ghostlight.** In *Ghostlight* (2024), directed by Kelly O'Sullivan and Alex Thompson, Kupferer played Daisy, the teenage daughter of a grieving construction worker who finds catharsis in a community theater production of *Romeo and Juliet*. The role came about after her father, cast as Dan, emailed the filmmakers to ask whether his daughter could audition; O'Sullivan said they did a reading with her and "cast her right away."[2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/) The film premiered at the 2024 [Sundance Film Festival](https://www.edgepedia.org/sundance-film-festival) and cast the real-life family, Keith Kupferer, Tara Mallen, and Katherine, as the on-screen family. Reviewers singled out her performance: Cinema Femme called it a "breakout turn," and MTR Network described her as "the breakout star of this film."[2](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/) • [9](https://www.mtrnetwork.net/ghostlight-review/)
**Mouse.** Kupferer plays Minnie Dunn, an introverted Arkansas high-schooler who loses her best friend, in *Mouse* (2026), the third feature from O'Sullivan and Thompson. The film premiered at the [Berlin International Film Festival](https://www.edgepedia.org/berlin-international-film-festival) and is scheduled for United States theatrical release on November 13, 2026, through Independent Film Company.[5](https://awardswatch.com/mouse-review-sophie-okonedo-and-katherine-mallen-kupferer-shine-in-tender-portrait-of-grief-and-growing-up-b-berlinale/) • [10](https://www.independentfilmco.com/films/mouse) Reviews again centered on her work: AwardsWatch wrote that she "anchors this tension with remarkable restraint" and called her "a true standout," and the [BFI London Film Festival](https://www.edgepedia.org/bfi-london-film-festival) program said Kupferer and co-star [Sophie Okonedo](https://www.edgepedia.org/sophie-okonedo)'s performances "drive this beautiful film."[5](https://awardswatch.com/mouse-review-sophie-okonedo-and-katherine-mallen-kupferer-shine-in-tender-portrait-of-grief-and-growing-up-b-berlinale/) • [11](https://whatson.bfi.org.uk/lff/online/default.asp?BOparam%3A%3AWScontent%3A%3AloadArticle%3A%3Apermalink=mouse-lff26) In an interview around the film's release, she said that unlike her *Ghostlight* character, who felt close to herself, Minnie was different enough that she had to develop her acting technique.[12](https://www.fred.fm/mouse-interview-with-actors-katherine-mallen-kupferer-and-sophie-okonedo/)
## Equestrian interests
Outside acting, Kupferer rides competitively. Her resume lists English riding, jumping 2'6" to 2'9" proficiently, a United States Pony Club D-3 rating, and competition in combined training events at the novice level.[3](https://www.katherinekupferer.com/uploads/9/5/0/1/95012444/katherine_mallen_kupferer_resume_7_21.pdf) She took fourth place in the Beginner Novice division at the Kent School Horse Trials and owns a Quarter Horse-[Thoroughbred](https://www.edgepedia.org/thoroughbred) cross named "Bay Is The New Black," known as Piper.[6](https://gigmarketing.us/katherine-mallen-kupferer.html)
## References
1. [Katherine Mallen Kupferer, TV Insider](https://www.tvinsider.com/people/katherine-mallen-kupferer/)
2. [This is Our Family: Tara Mallen, Keith Kupferer and Katherine Mallen Kupferer on "Ghostlight," Cinema Femme (2024)](https://cinemafemme.com/2024/06/10/this-is-our-family-tara-mallen-keith-kupferer-and-katherine-mallen-kupferer-on-ghostlight/)
3. [Katherine Mallen Kupferer resume, official website](https://www.katherinekupferer.com/uploads/9/5/0/1/95012444/katherine_mallen_kupferer_resume_7_21.pdf)
4. [Katherine Mallen Kupferer, IMDb](https://www.imdb.com/name/nm10102806/)
5. ['Mouse' Review: Sophie Okonedo and Katherine Mallen Kupferer Shine in Tender Portrait of Grief and Growing Up, AwardsWatch (2026)](https://awardswatch.com/mouse-review-sophie-okonedo-and-katherine-mallen-kupferer-shine-in-tender-portrait-of-grief-and-growing-up-b-berlinale/)
6. [The Flair Q&A: Katherine Mallen Kupferer, Gig Marketing (2023)](https://gigmarketing.us/katherine-mallen-kupferer.html)
7. [All Keith Kupferer series and films, BetaSeries](https://www.betaseries.com/en/person/185489-keith-kupferer)
8. [In 'Ghostlight' a real-life family plays their reel selves, KOSU (2024)](https://www.kosu.org/arts-culture/2024-06-16/in-ghostlight-a-real-life-family-plays-their-reel-selves)
9. [Ghostlight Review, MTR Network (2024)](https://www.mtrnetwork.net/ghostlight-review/)
10. [Mouse, Independent Film Company](https://www.independentfilmco.com/films/mouse)
11. [Mouse, BFI London Film Festival 2026](https://whatson.bfi.org.uk/lff/online/default.asp?BOparam%3A%3AWScontent%3A%3AloadArticle%3A%3Apermalink=mouse-lff26)
12. ["Mouse", interview with actresses Katherine Mallen-Kupferer and Sophie Okonedo, Fred Film Radio](https://www.fred.fm/mouse-interview-with-actors-katherine-mallen-kupferer-and-sophie-okonedo/)
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*Topic: Encyclopedia › Arts and culture › Screen and stage › Film and television › Screen people and creators › Child and youth screen performers › Child performers born 2001 to 2010 › Performers born 2006 to 2010*
*Initially written Sep 17, 2026 · Reviewed: Oct 25, 2026 · Edited: Oct 12, 2026; Oct 15, 2026; Oct 25, 2026 · Last review: Oct 25, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license