Morag Siller, who has died of cancer aged 46, was a busy Scottish-born actress who appeared in numerous television soaps and stage productions.

In Coronation Street (2013) she played the Reverend Esther Warren, the vicar who officiates at a christening service which is dramatically suspended following a row about the child’s parentage. In Emmerdale in 2002 and 2004 she was Marilyn Dingle, the wife of Elvis and mother of Brando. As the wonderfully named champagne-swigging Flora Kilwillie in Monarch of the Glen (2000-2), she recalled spending most of her time “getting bitten by midges and falling in lochs”.

In 1999 she was cast in Casualty for just one episode, as Leona, a lonely bag lady who drinks too much and screams a lot, but the scenes between her and Charlie (Derek Thompson), the lynchpin of Holby General A&E, convinced the producers to invite her back and she became a regular guest on the show.

The character of a homeless woman with no family of her own appealed to Morag Siller because she too had known how it felt to be isolated, having been adopted, along with a twin brother, shortly after their birth in Edinburgh on November 1 1969.

She also had two older sisters and a brother who were adopted separately. Although she made contact with her birth mother later, she never learnt why she had been put up for adoption and, as a child growing up in affluent Morningside, she felt an outsider.

None the less, she reflected that being adopted had probably been the best thing that had happened to her and admitted that another reason she was so grateful for her part on Casualty was that it made her adoptive mother, a nurse, proud. “There’s me, desperate to get on the stage of the National Theatre or the RSC, but because Casualty is her favourite show my mum was over the moon,” she said.

She was educated at James Gillespie’s High School, where she wanted to be a policewoman, but got bitten by the acting bug when, on her way home from school, she came across a television crew filming an episode of Taggart: “I just remember thinking: 'I want to do that’… A few of my friends had been asked earlier to be in background scenes, but I had been too late. I was gutted.”

She joined Edinburgh Youth Theatre and took classes at the Edinburgh Acting School with the future This Life star Daniela Nardini. Leaving school at 17, she headed for London, where she trained at the Sylvia Young School and at Rada.

While still a student she landed a role as a jitterbug dancer in David Puttnam’s film Memphis Belle (1990) and went on to appear on stage in touring productions of Les Misérables (1997-8, as Madame Thénardier) and the musical Mamma Mia! (2006) in which she played Donna’s chubby best friend, Rosie. Last year she was the Danish ambassador Voltemand, dispatched to negotiate with the King of Norway, in the controversial production of Hamlet at the Barbican.

On television her credits included Hetty Wainthrop Investigates and The Bill. Her most substantial role was as Karen, the troublesome daughter of Vera Small (Anne Reid), in two series of Ladies of Letters (ITV, 2009-10), also starring Maureen Lipman. Last year she made a brief appearance on EastEnders, as Muriel Rhodes, an antenatal class teacher.

In 2005 she married Tim Nicholson, a classical musician. They had been about to adopt a child in 2011 when Morag Siller was diagnosed with breast cancer.

She became a patron of two cancer charities, for which she organised fundraisers, and had hoped to resume the adoption process. But the cancer returned and she was told it was incurable.

Her husband survives her.

Morag Siller, born November 1 1969, died April 15 2016