A debut novel about a refugee whose new classmates embark on a quest to find their friend's parents has won the Waterstones Children's Book Prize.
Onjali Q Raúf's The Boy At The Back Of The Class, won the £5,000 prize, which was inspired by people she met while working in refugee camps.
Waterstones children's buyer, Florentyna Martin, described the novel as a "future classic".
Tomi Adeyemi's Children Of Blood And Bone won the older fiction category.
The illustrated book prize went to The Girls by Lauren Ace and Jenny Løvlie.
Raúf is founder and CEO of Making Herstory, a human rights organisation working in partnership with other movements to end the abuse, trafficking and enslavement of women and girls in the UK and beyond.
"Children's books have a raft of difficult topics to convey to young readers, and Raúf embraces this with an approach that is funny, upbeat and overwhelmingly open-hearted," Martin continued.
The Waterstones Children's Book Prize has been championing new and emerging talent in children's writing for 15 years and the winners are voted for solely by booksellers.
Last year's winning entry was also a debut work - Angie Thomas picked up the £5,000 prize for The Hate U Give, inspired by the Black Lives Matter movement.
It went on to become a successful film of the same name.