Inspired by the daily scud of clouds across the sky, best pals Angie Moon and Harry Christmas are experts on weather fronts and formations of cloud, be it candy floss wisp or rain-swollen knot. Born two days apart, Angie thinks of Harry as her almost-twin, but their easy, uncomplicated friendship is about to be tested beyond endurance when recurring headaches lead to a grave diagnosis for Harry. Cloud Boy by Marcia Williams is a touching and unusual story of love and resilience. Keep a tissue to hand.

Written in diary form by Angie, many entries begin on a meteorological note and I love the way clouds are woven through the narrative, in both an actual and metaphorical sense. For Angie, spotting cumulus clouds in the morning foretells a positive day, their fluffiness being perfect for finding animal shapes in.

We perceive that Harry’s least favourite cloud, Nimbostratus, is the one that increasingly squats in his thoughts. Comparing it to a mist in the head, he loathes the cloud formation’s heavy, unyielding darkness. The mist in Harry’s own head continues to grow and he’s admitted to hospital for a vital operation. How Angie supports her beloved friend while dealing with her own anguish and fear makes for a striking read.

Some much needed TLC arrives in the fine form of Angie’s Grandma Gertie. Helping her granddaughter create a special memory quilt for Harry, Gertie provides solace and wisdom as Angie grapples with her fear that Harry is drifting away.

‘Last night I lay in bed and imagined I was on a cloud with Harry…As I closed my eyes, Harry became part of the cloud, pale and wispy. He was there but only just.’

Sensitive souls may find this an emotional read in which case it may be better read alongside a reassuring parent. Leavened by humour, courage and often joy, despite the clouds there is much sunshine in this memorable book.

Cloud Boy by Marcia Williams is published by Walker Books, 208 pages.