‘Read these.’ I wave a wad of A4 paper towards Vanessa, creased from being stuffed into my bag. Last night when I got home from Nathan’s, I’d spent hours Googling, printing off page after page of true-life stories, Blu-Tacking some of them to my wall among the photos of Callie. The magnolia paint in my kitchen is barely visible any more.

‘Jenna, I understand you believe there is such a thing as Cellular Memory…’ says Vanessa.

‘It is a thing.’ I spring to my feet, hands balled into fists by my sides. ‘There are many scientists and doctors, and these are growing in number all the time, who support the theory memories can be stored in the neurons of the heart and transferred to the recipient. New science is testing the theory that the heart is involved in our feelings. It has already shown the heart has intelligence.’

‘But it’s not actually proven that Cellular Memory…’

‘It is proven that memory itself is distributed throughout the neural system, and the heart’s nervous system contains around 40,000 neurons that communicate with the brain. If you transplant a heart you are also transplanting these neurons.’ I’d stayed awake half the night filtering facts, trawling through medical jargon, trying to understand. I continue: ‘There was a paper published in Austria by the Quality of Life Research which documented that twenty-one per cent of heart transplant patients who were part of the study experienced a change to some degree. Twenty-one per cent! That’s huge.’

‘Please sit down.’ Vanessa’s tone never changes. She may raise an enquiring eyebrow and look over the top of her glasses in that way of hers that makes you question everything, but her voice is always the same.

I ignore her and stride over to the window.

‘How are you finding being back at work?’

‘You can Google it too.’ I’m determined not to let the subject drop. ‘Cellular Memory is…’

‘Jenna, I can’t…’

‘You won’t.’ I spin around to face her. ‘Please. Just read the medical journals. At Honolulu University, Hawaii, the School of Nursing carried out research and they documented that all of the heart transplant patients who were part of the study changed in ways that were parallel to the donor’s history, not just their tastes either, their sensory experiences too. There are thousands of real-life cases online as well where people receive an organ and it changes them.’

‘Of course it changes them. It gives them a second chance of life.’

‘Of whose life? Theirs? Their donors?’

‘It’s not possible that…’

‘There’s a case where a British woman woke after her op speaking fluent Russian. She’s never been to Russia. The donor was Russian. Another where a boy found he could play piano, as good as any concert pianist – he’d never tried an instrument in his life. I’m not making this up.’ This morning I’d silently recited the facts to myself over and over, knowing I needed to present them calmly to have any hope of being taken seriously. Instead, I trip over my words in a rush to get them out. My voice is too high and too fast.

‘I’m sure you’re not making it up, but scientifically…’

‘Scientifically it’s impossible that a teenage girl can receive a transplant and get behind the wheel for her first driving lesson and drive like Lewis Hamilton. Her donor was a racing driver.’ It sounds ludicrous I know, but I desperately want Vanessa to believe me. I sink back onto the sofa. ‘Look.’ I calm my voice. ‘It’s not only massive changes for people. It’s small things too. Craving food they never ate before, listening to new music, reading in different genres. If recipients meet the donor’s family, they often find out that the new things they are trying were the donor’s favourite things. Scientists are taking it seriously, why can’t you?’

‘But tastes do change. And it’s only natural that being given a second lease of life would lead to wanting new experiences. To live as much as possible. Trying new books and music is part of that.’

‘But there’s strange dreams, memories of things that haven’t happened, yet they all turn out to have happened to the donors.’

‘People experience the same things all the time without knowing it. Not many experiences are brand new.’

‘I felt such a bond with Nathan. Like we were connected somehow.’

‘And he felt this too? This connection.’

At Nathan’s house, I’d been in a daze during dinner as I twirled spaghetti around my fork, and I’d left as soon as he’d cleared the plates. We hadn’t swapped numbers, and I’d sent him a Facebook friend’s request this morning but he hasn’t responded. Tom and Amanda haven’t been in touch either. These people I feel tied to have let me go so easily. Is it all in my head? I ignore Vanessa’s question and press forward.

‘What about my episodes? The fear? The panic? The things I think I can see? It’s like they’ve happened before. What if they have, but not to me? To Callie? It’s a possibility, isn’t it? I’m not going mad, am I?’

‘You’re not mad, Jenna, but you have been through an incredibly harrowing experience and you’re on very strong medication. Your mental health has suffered. Understandably so. We’ve talked about relaxation, haven’t we?’

I ignore her question. ‘What about my dream? Playing Poohsticks on the bridge. The picnic.’

‘I think everyone has played Poohsticks at some stage. It’s probably an old memory resurfacing from when you were small.’

I didn’t have sex in a cornfield when I was small, I think, but I can’t tell her that part of my dream. It’s too embarrassing.

‘So why would I have remembered it now. Just before I met Nathan?’ No matter what Vanessa says it doesn’t make sense.

‘Who knows? There are lots of things that can cause the subconscious to nudge something back to the conscious mind. A smell. A sound. A feeling.’

‘It’s too coincidental.’ I lean forward, pulling the sleeves of Sam’s green fleece over my hands, resting my elbows on my knees that jig up and down.

‘That’s often how memories are recalled. Subtly. Have you ever seen one of Derren Brown’s shows? He uses triggers to coax the mind in a certain direction. He knows what people are going to say and do because he’s engineered their response. Planted visual and auditory stimuli. It’s not unlikely that your memories were triggered the same way.’

‘But I don’t think they are my memories. I think they’re Callie’s. The dreams when I’m on the beach with another little girl – I think that’s Sophie. Her mum had paintings on the wall of girls on a beach. The picnic. The man. That must be Nathan.’

‘Let’s suppose for a minute you are dreaming Callie’s memories.’ Vanessa’s face is neutral, and I know she is humouring me. ‘What does she feel? With this man? This little girl?’

‘Happy.’

‘Would you consider the possibility that your deep-rooted guilt with regards to Callie’s death could be manifesting in your dreams? Showing you she had a happy life to help ease your conscience?’

I think about this for a moment; it does seem plausible. ‘But it feels so real. I believe she’s trying to tell me something but it’s so muddled. The dreams are happy but the snippets of memories that flash when I am awake are so dark. She was scared of something. Or someone. I’m sure.’

‘Do you feel scared, Jenna? Not Callie. You.’

‘Sometimes.’

‘And the dreams you are having. Let’s take the one of you playing on the beach. How did that make you feel?’

‘Less lonely,’ I admit. Growing up I’d always wanted a sibling. ‘And…’ I trail off. My face flushes as I think of some of the other dreams I’ve had with the man in them. I don’t want to tell Vanessa that I can still feel his warm fingers on my skin when I wake and my body burns with the desire to be touched. Could it be just my subconscious whispering to me? Cellular Memory seemed so real to me an hour ago. Now I’m not so sure.

‘Are you lonely?’

‘No. Yes. A bit, I suppose.’

‘The world can seem a scary place when you’re already feeling alone. All of the emotions you’re feeling are entirely yours, Jenna. You have to own them in order to move forward. You’ve been through a very difficult time. You nearly died. Your relationship with Sam broke down. Your parents have separated. Any one of those incidents on their own can cause severe stress. All of them together, it’s no wonder you’re fraught.’

‘But Callie…’

‘Becoming fixated on Callie is not going to help you. My heart goes out to her family, it really does,’ Vanessa says. ‘It’s very commendable donating organs but you need to find a way to make peace with what’s happened. Callie would have died anyway, whether she donated or not. This…’ She taps her pen against my notes. ‘This is why we try to discourage any contact other than a thank you letter. It’s too emotional. For everyone. I strongly advise against having any more contact with her family. I don’t want to sound uncaring but you’re my main priority, Jenna. You have to put your own emotional well-being first.’

‘But my picnic dream…’ I’m wavering now. ‘I couldn’t stand strawberries before I had that dream. Now I can’t stop eating them.’

‘Tastes change as we get older. I used to parcel my Brussel sprouts in a tissue and hide them in my pocket but now I love them.’

‘It’s hardly the same thing.’

‘I’m not a dietician, but cravings can be triggered by hormone imbalances and deficiencies. Your body knows what it needs. Strawberries are a healthy choice and not something to worry about.’

‘But… listening to Abba.’

‘Now that may be something to worry about.’ Vanessa winks at me to show she’s joking and then puts her clipboard and pen on the table in front of her. ‘Sorry, Jenna. The session has flown past. I know you’re concerned and I do take it seriously. Journal your thoughts, make a note of anything else you think is strange and bring it along next week. We’ll go through it together. In the meantime, please try to relax.’

She stands, and I know I’m not going to find the answers I need here. She doesn’t believe me. But something’s happening to me and I’m determined to find out what.

As I turn to walk out of the door she says: ‘Let Callie go, Jenna.’

But what if Callie won’t let me go? I want to ask. But I don’t. And an icy chill brushes against the back of my neck.