If you’re a children’s writer, you’ve got to be alive to the child in you – one part of your brain is forever tuning in to the rhythms and images that worked for you when you were small. Your own kids can help in this regard too. Now that Belle and Arthur are eleven and seven respectively, I can ask their opinion on things. They can tell me what works and what doesn’t. Best of all, they can help fuel my repository of stories and ideas. My current series, Lockwood & Co., concerns a group of teenage ghost-hunters in an alternative London. They encounter all kinds of terrible apparitions, and I need to keep these nicely varied. What better way than to rustle up some horrid phantoms with my kids while out on long walks? We take it in turns telling ghost stories as we go, and Belle and Arthur between them have come up with some classics: The Floating Fingers and The Twisted Ghost of the River Thames (see pic) to name but two. Often their ideas are even more horrid than anything I can come up with, which is both reassuring and a bit worrying.

And Isabelle has got to the next stage. She’s given me one bona fide top bit of inspiration for Lockwood & Co. My heroes live together (without adults) in a house in Marylebone. Their kitchen table is covered with a white tablecloth, on which they write and draw with pens – passing on messages, sketching ghosts and figuring out mysteries, all while chomping on their midnight sandwiches. This ‘Thinking Cloth’ is really important to the plot, and is a running theme in the series. And it was Belle’s idea. Goodness knows what other delights she and Arthur will come up with over the next few years. Every author needs a trusted audience – both to bounce ideas off and to be inspired by – and I’m fast learning that my children are the most perfect audience of all.

The latest book by Jonathan Stroud, Book 2 in the Lockwood & Co. Series – The Whispering Skull – is available to order online today as a Paperback, Hardback and eBook. Follow Jonathan on twitter: @JonathanAStroud or visit his website www.jonathanstroud.com.