Question: Who co-starred in the 2003 British comedy with the actor who co-founded Baby Cow Productions?

Context paragraphs:
Marion and Geoff: Marion and Geoff is a BBC television mockumentary, produced by Baby Cow Productions and screened on BBC Two in 2000, with a second series following in 2003.  The series starred Rob Brydon as Keith Barret, a naïve taxi driver going through a messy divorce from his wife, Marion, who, though he fails to realise it, has had a long-standing affair with her colleague, Geoff.  Each episode is presented as a monologue, filmed by a fixed camera in the confines of his cab.

The Private Life of Samuel Pepys: The Private Life of Samuel Pepys is a 2003 British comedy television film directed by Oliver Parker and starring Steve Coogan, Lou Doillon and Nathaniel Parker.  It portrays the historical diarist Samuel Pepys.  It was aired on BBC2 on 16 December 2003, drawing an audience of 2.9 million viewers.

Cruise of the Gods: Cruise of the Gods was a one-off comedy/drama produced by Baby Cow Productions for the BBC.  It starred Rob Brydon, Steve Coogan, David Walliams and James Corden.  It aired in 2002 and has since been released on BBC DVD.

Ideal (TV series): Ideal is an English dark comedy-drama, originally broadcast on TV channel BBC Three, created by Graham Duff and produced by BBC Comedy North and Baby Cow Productions.  It stars Johnny Vegas as small-time cannabis dealer Moz.

Baby Cow Productions: Baby Cow Productions Ltd is a British comedy television production company established in 1999 by Steve Coogan and Henry Normal based in London and Manchester.  It has since diversified into radio, animation and film.  In 2008, BBC Worldwide bought a 25% stake in the company.  The acquisition was made at a time when BBC Worldwide was being criticised for its "out of control" ventures, though Normal told "The Guardian" that BBC Worldwide had not made the highest bid.  The company's name is a reference to Coogan's early characters Paul and Pauline Calf.

Moone Boy: Moone Boy is an Irish sitcom created, co-written by and co-starring Chris O'Dowd for British broadcaster Sky.  The series is co-written by Nick Vincent Murphy and is produced by Baby Cow Productions, Sprout Pictures, Hot Cod Productions and Grand Pictures.  The series is semi-autobiographical of O'Dowd and focuses on a young boy's life growing up in Boyle, County Roscommon in Ireland in the late 1980s and the early 1990s.  "Moone Boy" is the second series produced from Sky1's "Little Crackers" shorts and is inspired by O'Dowd's contribution, "Capturing Santa", which was produced by Sprout Pictures.

Steve Coogan: Stephen John Coogan (born 14 October 1965) is an English actor, stand-up comedian, impressionist, screenwriter, and producer.  He began his career in the 1980s, working as a voice artist on the satirical puppet show "Spitting Image" and providing voiceovers for television advertisements.  In the early 1990s, he began creating original comic characters, leading him to win the Perrier Award at the Edinburgh Festival Fringe.  In 1999, he co-founded the production company Baby Cow Productions.

Mid Morning Matters with Alan Partridge: Mid Morning Matters is a British digital radioshow parody written by Steve Coogan, Neil Gibbons, Rob Gibbons and Armando Iannucci, produced by Baby Cow Productions and funded by the British arm of Australian lager company Foster's, starring Coogan as fictional radio DJ Alan Partridge.  The first of twelve 15-minute episodes was uploaded to the Foster's Funny website on 5 November 2010, and then available on YouTube.  Six 30-minute episodes titled "Alan Partridge Mid Morning Matters: Special Edition", edited from the web series, began airing on Sky Atlantic HD in July 2012 as part of a deal between producers Baby Cow and BSkyB.  A second series consisting of six episodes was announced on 1 July 2014 to air on Sky Atlantic in 2016 with a premiere date of 16 February.

Nebulous: Nebulous is a post-apocalyptic science fiction comedy radio show written by Graham Duff and produced by Ted Dowd from Baby Cow Productions; it is directed by Nicholas Briggs.  The series premiered in the United Kingdom on BBC Radio 4.  Set in the year 2099 AD, the show focuses on the adventures of the eponymous Professor Nebulous, director of operations for the eco-troubleshooting team KENT "(the Key Environmental Non-Judgmental Taskforce)" as they combat various catastrophes and try to set the world back on the right path following a worldwide environmental disaster known as "The Withering".  As well as being a parody of a number of famous science fiction programmes, including "Doctor Who", "Quatermass" and "Doomwatch", "Nebulous" is considered a cult radio programme, attracting a number of guest appearances from famous actors.

The Abbey (TV series): The Abbey is a British television situation comedy produced by Baby Cow Productions for ITV, about dysfunctional celebrities with various vices that seek sanctuary at The Abbey to overcome their problems.  It is written by Morwenna Banks, directed by Johnny Campbell and executive produced by Henry Normal.

Supporting paragraphs: The Private Life of Samuel Pepys Steve Coogan
Answer: Lou Doillon and Nathaniel Parker