A Perfect Cornish Christmas. Phillipa Ashley

telly, complete with its tree logo and banner announcing:

       Discover your roots with TreeFynder!

      She cringed at the cheesy copy on the ancestry website. Privately, she’d have loved to rewrite it all and get a new design done – as with most websites – but that was for another day.

      Marcus and her parents sat back, intent on the TV screen. Heidi crossed her legs and smiled. ‘Gosh, the suspense is killing me.’

      ‘All will become clear,’ Scarlett said dramatically, ignoring Heidi’s sarcasm but slightly disappointed by the baffled expressions of the rest of the family.

      She logged on and the screen flashed up a message:

       Congrats! Here is your Latham family tree!

      ‘A couple of months ago, Ellie and I decided to have our DNA tested, so we could find out our genetic roots, and we really will know if Dad’s a Viking.’

      Marcus let out a whistle. ‘Now this is interesting. I’ve always wanted to do this.’

      Re-sult, thought Scarlett in triumph. ‘Right. Deep breath, because neither Ellie nor I have looked at the results. We thought it would be more of a surprise for everyone that way.’

      ‘It’s been so hard not to check out the site,’ Ellie said.

      ‘Without further ado, now we find out who our ancestors were. Ta da!’ Scarlett declared and tapped her mouse pad. At the same time, Ellie clicked on her own results on her phone.

      The silence could only have lasted a second or two, but it seemed far longer to Scarlett, already wound up to fever pitch after keeping the secret for so long.

      Her mother spoke first. ‘Um. This is very exciting, I’m sure, but what does it all mean?’

      Scarlett had spent so long on the TreeFynder site, learning how to interpret the potential results of the ancestry test, that she’d forgotten the figures and tables on the screen would mean nothing to anyone but her and Ellie. The actual findings were a complete surprise to her too, but she knew what they might mean in principle.

      ‘Well, both Ellie and I have had our DNA tested, which of course tells us about the rest of our relations and ancestors – and yours.’

      ‘Ah, I see.’ Marcus leaned forward.

      ‘How fascinating,’ Heidi muttered, picking up a magazine.

      ‘Obviously it doesn’t cover Heidi, but it will show the boys’ heritage too,’ Scarlett said, hoping to win Heidi over.

      Heidi let the magazine rest in her lap, her attention caught at last.

      ‘Yes, can you please explain this to those of us still stuck in the Stone Age,’ her father said.

      ‘OK. Well, Ellie and I sent off a sample of our DNA to this ancestry site and these are the results of their analysis. This chart shows the areas of the world and types of people who are our ancestors. It says that I’m 60 per cent Iberian, 20 per cent Irish and 20 per cent other ethnicity. So – no Viking …’

      Ellie held up her phone. ‘I am! Mine says I’m 70 per cent Scandinavian, 15 per cent Irish and 15 per cent other ethnicity.’

      ‘They’re very different. Is that normal?’ Marcus asked.

      ‘According to the guidelines, siblings can have very different genetic make-ups. Dad’s the Viking and Mum’s obviously the Mediterranean one. I have a different mix of Mum and Dad’s DNA to Ellie.’

      ‘That’s no surprise. You’ve always looked like Mum,’ said Marcus.

      ‘She certainly loves her Spanish holidays,’ her father said drily. ‘Now we know why.’

      Their mother flashed a smile. ‘Which reminds me, I must go and check on the potatoes.’

      Marcus, Ellie and Scarlett exchanged wide-eyed looks, wondering how potatoes could have anything to do with Spanish holidays.

      Anna got up, holding the tea towel she’d carried in from the kitchen.

      Ellie groaned. ‘Oh, don’t miss the best bit. The potatoes can wait, Mum.’

      ‘You won’t say that when you get a plate full of blackened lumps for lunch.’

      ‘I’ll check them,’ Heidi said, clearly looking for an excuse to get away from the family love-in. Actually, Scarlett didn’t blame her on this occasion and it might be less awkward if she wasn’t there.

      ‘Are you sure you can manage?’ Anna looked worried at the prospect of Heidi handling a tray of potatoes. ‘They are roasted in goose fat, you know …’

      ‘I’ll cope somehow.’ Heidi got up and patted her shoulder. ‘You enjoy your special present, Anna.’

      Scarlett wasn’t sure if her sister-in-law was being sarcastic or not, but she let it drop. Their mum sat back down on the sofa, still clutching the tea towel.

      ‘Now, here’s the really exciting part …’ She hovered the cursor over the Find Relatives menu. ‘Who knows. We might find some long-lost second cousins on here. Maybe we’re related to royalty, like Danny Dyer is.’

      Marcus groaned. ‘God, I hope not!’

      Their father laughed.

      ‘I don’t think we’re in line for the throne, Dad, but – oh look, we have a first degree relative on the site,’ said Scarlett. ‘What a surprise. Not.’

      ‘That’ll be me, of course,’ said Ellie, clicking her phone. ‘Because we’re both registered on their database … Let’s take a look. Oh, yes … oh …’ Her voice trailed off. ‘Oh.’

      ‘What?’ Scarlett asked.

      ‘I think I’ll go and help Heidi with the roasters.’ Their mother was halfway out of the door.

      ‘Mum, wait! Stay and see some more.’ Scarlett couldn’t conceal her disappointment. Then again, it was her father who loved history.

      ‘Sprouts need putting on!’ she shouted.

      ‘This early?’ Marcus laughed. ‘Come on, Ellie, show us this relative-finder thing.’

      ‘It, um … seems to have disappeared.’ Ellie held up a black phone screen and aimed a look at Scarlett. There was desperation in her eyes.

      ‘Don’t worry, I can get it up on the telly,’ said Scarlett, cheerfully.

      ‘Wait!’

      Ellie’s cry was too late. The 72-inch screen flashed up a notification.

       You have a half-sibling on TreeFynder.

      Marcus dived on it like a hawk. ‘Half-sibling? What’s that supposed to mean?’

      Ellie couldn’t suppress her gasp and exchanged a panicky glance with Scarlett. ‘That’s wrong. It’s not possible. We don’t have any half-siblings.’

      ‘It must mean sister or brother, of course,’ said their dad. ‘It can only refer to you and Ellie.’

      It must refer to her and Ellie. Half-siblings. Scarlett went cold all over as the implications sank in like wet slush soaking through the bunny slippers. Ellie stared at her; lips pressed together. When Ellie had seen the results on her phone, she’d tried to stop Scarlett from sharing them with the rest of the family.

      ‘It must be a mistake. Let’s try again.’ Faking a sigh of exasperation, Scarlett refreshed the page, hoping against hope it would miraculously show a different answer.