Tilly is a bit of a puzzle. She's struggling at school, she really doesn't like surprises, she isn't sure if she's a girl or a boy, and she just doesn't want to make new friends. Why is it such hard work to try and understand people, or for them to understand her?This poignant story maps the entire childhood of a bright young girl with autism. Growing up undiagnosed, she finds life increasingly difficult and confusing. Unable to communicate her thoughts and feelings, she retreats further into her own world while her family grows evermore perplexed and concerned. When a psychologist finally explains what makes her special, they can stop focusing on the problems and start to navigate a new way forward for Tilly.With vividly expressive illustrations and minimal words, this story is a valuable and accessible tool for helping children aged 7-13 and their families understand female autism, and will also be immensely helpful to readers interested in understanding better how autism manifests in girls. Honest, positive, and ultimately hopeful, it is inspired by the real childhood of Helen Bates's daughter Rachel, whose own writing describes her experiences as a girl like Tilly.