North Norfolk is the setting for a new Christmas novel by the cousin of Normal for Norfolk's Desmond MacCarthy, linking family secrets, long lost relatives and a deadly epidemic

A cosy family Christmas in the rambling ancestral hall on the East Anglian coast might sound idyllic – until a deadly disease, a dodgy engagement, bickering sisters, an unexpected brother and cancer crash the party.

For her first novel, Francesca Hornak has taken her real-life happy childhood Christmases, and stirred in a potent mix of modern make-belief.

Festive is transformed into festering as the family gather to spend the Christmas week amid the clutter and decay of a crumbling house, in quarantine from an ebola-type virus.

Francesca will be spending Christmas in Norfolk too – but is expecting a much jollier time.

'Until I got married I had never spent Christmas anywhere else!' she said. 'Our house is on the border of Wiveton and Cley, so the nearest towns are Blakeney and Holt. Every year we go to a candlelit carol service on Christmas Eve in Cley Church, and walk on Cley beach on Christmas morning.

'I've been spending holidays in Norfolk since I was born. I have lots of family on my mother's side on the north coast, including my cousin Desmond MacCarthy from the BBC series Normal For Norfolk.'

And she admits the house at the centre of her story, Seven Days of Us, is based on beautiful Wiveton Hall.

'Weyfield Hall is partly based on my cousin Desmond's house Wiveton Hall, where I spent a lot of time as a child, and where I got married. Wiveton Hall is in much better shape though – the shabbiest parts of Weyfield are based on other houses.'

With television rights to Seven Days of Us already sold, Francesca said: 'If it does get made I'll be hinting heavily that it should be filmed at Wiveton Hall!'

One of the sisters at the centre of Seven Days of Us is just back from treating victims of a deadly epidemic, so the family is in seven days of quarantine at Weyfield/Wiveton Hall.

The novel has already attracted praise from the likes of agony aunt Virginia Ironside, author Marian Keyes and blogger the Unmumsy Mum.

Francesca's fictional festive season is much darker than her own Norfolk Christmases, and the county itself is coloured gloomy, against a finale set back in the New Year sparkle of London. Francesca is happy to confirm she has never had a Christmas as fraught as her first foray into fiction.

'I really don't have any bad Christmas memories! My best childhood memories are of waking up to feel that delicious weight on your duvet of a fully stuffed stocking (my mother is a stocking expert) and of the ice cream bomb my father makes every year. It's rum and raisin, so it looks like a Christmas pudding in negative.

'My best recent Christmas memory is of getting married the week before Christmas, with a carol service in Wiveton church.'

This year she will be in Norfolk again – with her husband and their toddler sons, plus her parents, brother and godfather. 'We'll also have nine cousins over for lunch – and there are finally enough grandchildren for a 'kids table' which makes me feel very old!' she said.

Seven Days Of Us, by Francesca Hornak, is published in hardback by Piatkus for £12.99.