What if you could live your great love story again?

That's the question asked in Josie Silver's new heartbreaking (and beautiful) new novel, The Two Lives of Lydia Bird.  The book follows the inseparable Freddie and Lydia, who have been together for nearly a decade - and are just about to say 'I do'. But then, on Lydia's 27th birthday, Freddie dies in a tragic accident. Then something unbelievable happens. Lydia gets another chance at her old life with Freddie. But what if there's someone in her new life who wants her to stay? "My editor kind of gave me a brief of what she was thinking about, and with this one, we were talking about how sometimes you can have that moment where even a small thing can happen that makes all the difference," the author told Her, as she discussed the inspiration behind the book. "Kind of like a sliding door moment. And in the book, that's the point where Freddie makes the decision to go pick up Jonah - and that's the decision that [changes everything]. That's what we were looking for, something that started with an insignificant decision that made all the difference. "And then the sliding door, that came into it with how would her life be different if that hadn't happened? And obviously, how it did happen - it's that whole parallel light idea, where she's with him in one life and in other life, she's tying to get on with her grief about how he's not there anymore." Following Freddie's death, Lydia is given sleeping tablets which, when she takes them, enable her to go to a parallel world where he lived - and where she gets the answers to all her "what ifs". Silver - who also wrote 2018's One Day In December - told us how she tried to "strike a balance" between the time spent in Lydia's real world and her sleep world. At least, in the beginning. "It's such an [intriguing] idea, that you can get the person that you've loved and lost, so obviously in the beginning, she was going to try to spend as much time as possible - as anyone would - with the person that she'd lost, as she had gotten this wonderful chance to have him back again," she said. "So, I think it was necessary for the beginning of the book, for her to spend as much time as possible in the sleeping life. And then only as the story goes on, and she starts to realise that the person that she's becoming in her waking life isn't necessarily the same person anymore. Obviously, because she's had to adapt and change and grow in her waking life - and then trying to step back into her old shoes in her sleep life  because she's in her waking life and then tried to step back into her old shoes, in her sleep in life, she finds that they rub. She's not quite fitting in in the way that she used to. The balance between the sleep life [and the waking life] was heavier at the beginning - but I think, naturally, she needed to come to terms and live a little in her awake life as the story progressed." [caption id="attachment_501809" align="alignnone" width="1463"] Photo by Justine Stoddart[/caption] The relationship between Lydia and her sister Elle is one that readers will find incredibly relatable. It will have readers laughing out loud on one page, and tug at the heartstrings on the next. And, as it turns out, it's one that was inspired - in part - by a relationship in the author's real life. "Probably the sister relationship, I would say the most. I'm fortunate to have an older sister, she's 18-months-older than me - and she's my best friend. I didn't have to look very far for that, it was very much informed by my own relationship with my sister," she said, noting how she loved writing the siblings as they were "just two peas in a pod." "And it's the same with families, as well. You know, I'm really fortunate, really strong family around me, and I tend to put that in the book - not the actual people themselves, but just that, that support and that love." Silver's debut One Day In December was a Sunday Times and New York Times bestseller - and The Two Lives of Lydia Bird already has fans falling head-over-heels in love. In good news for fans of her work, the author told us a bit about what fans can expect from her next novel. "I can't really say much at the moment, but I can tell you the title. It's a working title so it may change, but at the moment it's called 43 Love Letters," she said, before sharing a small bit  about what the novel is about. "It's a big, kind of love story that is to do a lot with parenthood, motherhood and marriage - but beyond that, I can't really share too much."

• The Two Lives of Lydia Bird, published by Penguin, is available in stores now.