Morna and Helen Mulgray, 69, live together in the Portobello district of Edinburgh. Since they retired from teaching English they have pursued joint careers as crime writers the Mulgray Twins, the only twin pair of authors in the world.

Morna

Mother only expected one child. She had been unwell, something to do with blood groups, so out we came a month premature and Father had to go and phone their friends to say yes, the baby had arrived and there were two of us.

We were born in 1939, so there was the war to consider. Dad was considered older, at 36, so he wasn’t called up until 1941 but he worked as a warden until then. I remember Daddy going out to “see the lights are out” when we were small and then we didn’t see him again until 1945. He was a complete stranger.

What do I remember of those days? Playing together at nursery while my mum worked as a librarian. Happy times, oh yes. We loved imaginary games, books with little character figures and dice so you could decide on their adventures.

Occasionally there was a dispute, but rarely. We played with other children of course, but we had severe measles at the age of three so we were fragile in health. We were ill so often we attended a special school with children with spina bifida, epilepsy, that sort of condition. If there was an illness going around we got it. Mother had a terrible time of it.

The fashion now is to send children with disabilities through mainstream education, but I think it’s a mistake. We had the individual attention we needed. If we were off school, we carried on at the same spot where we left. And we read a lot in bed, books now considered too difficult for children, Kidnapped, Treasure Island, and we loved Enid Blyton.

Father died in 1965; Mother in 1975, it was an adjustment, but you are never alone when you have a twin. The first time we had to separate to any degree was at Edinburgh University when we attended different lectures. It was odd to walk down a street by myself, as if something was missing from my side.

I can’t describe her as a separate person, she’s the same as me. There is that special bond. There have been men, but nothing felt quite right. People marry for companionship as well as, I suppose, sex, and if you have the perfect companion already, who can measure up?

Helen

Where they got the name Morna from I don’t really know. She was going to be called Wilhelmina, so I’m glad they changed their minds.

We don’t much like being separated — every so often it would be attempted and wouldn’t take. They tried to split us up for science class, so we both gave up the subject. It’s a subtle form of jealousy, I think, of the special relationship twins have, this desire to separate them.

We’ve both taught twins. At some point they find their independence if that’s what they want, no point forcing them into it. At school, teachers couldn’t tell us apart so we wore a big brass H or M on our lapel. Of course, they said we’d swapped them over.

We no doubt intended to get married if the right person came along, but they didn’t. Morna had somebody who proposed, but she turned him down. I thought it was the right decision — she hardly knew him. If it had been the right person, I would have been happy for her.

Our mother was someone to go to for advice, so when she died it felt like a big step. We took great holidays together, to the Seychelles, Hawaii, Penang, amazing places and we took pictures which we turned into posters. One of Morna in a bikini sitting in a wicker chair, sipping something delicious out of a cocktail glass was a favourite in the schools where we worked.

In Hawaii we started writing this romantic humorous thing, hoping Mills and Boon might like it. We sent it off to various people, but it was agreed that there were too many jokes. You have to have the hero and heroine on every page . . . pfffshaw. Not our genre, we’re much happier with murder.

After we took early retirement in 1993, we thought about doing it more seriously. Still a hobby, but we wanted to finish what became our first novel, Not Suspicious Circumstances. Six years later . . .

People ask how we write together, it seems obvious to us but evidently isn’t to others. One types part of a sentence, and the other says ‘That’s all right’ or ‘No, change that’ and between us we get a sentence out. We have a target of 250 words a day, absolutely minuscule.

It’s impossible to describe Morna without describing myself. Is she a good person? Yes, I think so. Funny? To me, definitely. Maybe we’re just scared to say more in case the other gives us a black eye. We do have to live together, remember.

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