Books can help us navigate our way through life. People who don’t read can get on well of course, but having books with you along the way can help hugely. I can’t think of a greater challenge in life than the transition to adolescence, and I equally can’t imagine how amazing it would have been to have made that journey with the Tiffany Aching novels by my side. Because this series is about growing up, not in a self-conscious ‘so here’s how to deal with bullies’ way, but by sharing Tiffany’s story.

A Hat Full of Sky is the sequel to the Wee Free Men. Tiffany, now eleven, is leaving family and home to train as an apprentice witch. Leaving her beloved Chalk, the land of her childhood, is hard for her, leaving behind everything that is comfortable and familiar. She goes to live with Miss Level, a witch who has two bodies ( a nice twist on the split personality idea) and a poltergeist named Oswald who cleans the house (another clever inversion).

Tiffany’s powers are such that unknown to her she is being hunted by a dangerous magical creature, a hiver, an ancient parasitical paranormal entity. She is particularly vulnerable when she uses her powers to step outside her body, which she does innocently to look at herself.

Settling in to her new home she meets a group of apprentice witches – far from dying out, witchcraft in this part of the world seems to be thriving. As the new girl she faces the usual struggles of fitting in. The patronising and rude self-appointed leader of the group, Annagramma could be found in any playground in the world. Tiffany represents a potential challenger to her top-dog status, having already met Discworld’s greatest witch, Granny Weatherwax, and been given a hat by her, albeit an invisible one (hence the novel’s title). The other girls don’t believe her, and are mean. Upset by this encounter, Tiffany is vulnerable and is taken over by the hiver. Being possessed by the hiver makes her feel powerful but dangerous, almost like taking drugs?

You can read Tiffany’s struggles with the hiver as a metaphor for depression, anorexia, or any other mental health problem. Young women in particular are vulnerable to doubts about their value, even their identity. That vulnerability can leave them open to ideas or other things that are superficially empowering but nonetheless harmful. Pratchett doesn’t overwork this concept – Tiffany doesn’t self harm for example – but she does struggle internally with the hiver, trying to assert her identity. Her small cries for help aren’t heard by her friends, although the Feegles quickly work out what has happened. Without ever being patronising or spelling things out, I think Pratchett gives his readers some practical ideas on how to deal with these issues in a way that is probably far more helpful than the self-help books that address these issues head-on.

Fortunately, Tiffany has a trump card, the Nac Mac Feegles, wonderful, unruly pictsies, sworn under a geas to defend her from harm. I love the fact that Pratchett is happy to make the geas/geese pun (more than once), even though it is such a terrible dad-joke. Rob Anybody, fearless leader of the Feegles, magically travels into Tiffany’s mind to help her fight the hiver. He works out that smells from her past will allow her to break from the hiver’s control (the scenes where the Feegles collect the items needed – tobacco, alcohol and wool – are a wonderful diversion). Tiffany wrests back control but is left with the memories of the hiver’s previous victims, which she uses to give her strength, drawing on them for support. With the help of Granny Weatherwax, visiting for the Witch Trials, Tiffany comes to understand that the hiver is not something that she needs to defeat but to come to terms with. I think this all works really well as an extended metaphor for how to deal with mental health problems.

I’ve talked a lot about this book being a guide to growing up. But as with all Pratchett’s novels the wisdom it contains is for all ages. I found this paragraph on leaving home quite poignant:

Why do you go away? So that you can come back. So that you can see the place you came from with new eyes and extra colours. And the people there see you differently, too. Coming back to where you started is not the same as never leaving.

And there’s also this advice, which initially appears to be quite witch-specific, but perhaps not:

“Always face what you fear. Have just enough money, never too much, and some string. Even if it’s not your fault, it’s your responsibility. Witches deal with things. Never stand between two mirrors. Never cackle. Do what you must do. Never lie, but you don’t always have to be honest. Never wish. Especially don’t wish upon a star, which is astronomically stupid. Open your eyes, and then open your eyes again”.

Finally, I have written many times about Pratchett’s ability to make me laugh out loud. Once again he managed to achieve this in the scene when Death appears, and is confronted by the pugnacious and profoundly loyal Rob Anybody:

“I WAS NOT EXPECTING A NAC MAC FEEGLE TODAY, said Death. OTHERWISE I WOULD HAVE WORN PROTECTIVE CLOTHING, HA HA.”

Glorious, precious, stuff. It’s easy to overlook the Tiffany Aching Discworld books as just for children, or ‘stories’ rather than novels, and I was probably guilty of this first time round, but now I am coming to appreciate them far more as fully-rounded additions to Sir Terry’s body of work.