Gillian Louise Kearney (born 9 May 1972, Liverpool, Merseyside) is an English actress best known for playing Jessica Harrison in the long-running BBC television medical drama series Casualty, and her early role as Debbie McGrath in Channel 4's Liverpool-based soap opera Brookside and the spin-off mini-series Damon and Debbie.
One of four children born to Gerard and Barbara (née Allerston) Kearney, Gillian Kearney has three brothers: Matthew, Peter and Tom, a professional footballer. Her father is a retired civil engineer and her mother a school care worker. Growing up in Aigburth, she attended St. John Almond RC High School, Garston, where she gained nine GCSEs and four A-levels.
Her interest in acting began at secondary school. After repeatedly being overlooked for the lead roles in school productions, she decided to join the Liverpool Everyman Youth Theatre, where she featured in plays including All Flesh is Grass (as Ema), Katie Crackernuts and Yer Dancin'? It was there, in 1986, that she was spotted by members of the production team at Mersey Television, an event that resulted in her being asked to audition for a role in Channel 4's Liverpool-set drama series Brookside. Kearney landed the role of Debbie McGrath, the girlfriend of Damon Grant (played by Simon O'Brien). When O'Brien decided to leave The Close, he requested that his character be killed off so he wouldn't be tempted to return to the show. Because Damon was so popular, particularly with younger viewers, it was decided to create a 'soap bubble' in which the character would meet his demise — Damon and Debbie became Britain's first mini-series spin-off from a soap opera. A year after filming her final scenes, Kearney was asked to return for a few episodes. Christmas 1988 saw Debbie McGrath make an unexpected return to visit Sheila Grant, Damon's mother; she arrived with her baby, Simon – Damon's son.
In 2002 Kearney landed the coveted role of June Forsyte in the ITV1 adaptation of John Galsworthy's classic novel, The Forsyte Saga. She later reprised the role for the second series. Following the success of The Forsyte Saga, Kearney's next role brought her back onto the ITV screen in its newest medical drama Sweet Medicine. Kearney was cast as Dr Deborah "Deb" Sweet and starred alongside Jason Merrells, who played her husband, and Patricia Hodgeas her formidable mother-in-law. The show was intended to take up the mantle of the popular rural drama Peak Practice, which had recently ended, but low viewing figures saw Sweet Medicine axed after just one series.
In 2005 Kearney landed a role in Channel 4 hit Shameless playing the role of Marty's girlfriend Sue. She left the show along with her on-screen partner in 2007. She had a number of television roles following her departure before landing the role of Jessica Harrison in Casualty, in January 2008. Kearney left Casualty in February 2010, but returned briefly to tie up the loose ends of her character's storyline in May 2010.