Sophie Hartley is almost sure that her dad said okay when she asked for a baby gorilla for her birthday. Soon the kids at school want to know every detail about the gorilla, and dealing with her enthusiastic classmates gets harder as the big day approaches. When teenage sister Nora leaves their shared bedroom for her own space in the attic, and close friend Jenna shows signs of becoming a shrieker, Sophie finds it hard to remain optimistic. Maybe painting her windowsills purple will help. And maybe she'll get the perfect present! Funny and believable, the story of a big birthday will please old and new Sophie fans.