"Cailin" is the Irish word for girl, and seemed a perfect title for this 40,000 word 'tweener' novel, since so much of our fantasy world is rooted in Celtic mythology. Sarah Grace Littleton, my step-granddaughter, can see fairies. The problem is, she can't really tell anyone. She's already in trouble at school, and the last thing she needs is more. But, a fairy named Fiona is buzzing in her ear, warning of dire consequences if Sarah Grace doesn't develop the power within herself to help save their two worlds. Sarah Grace's immediate world consists of her family, which includes her Grammy, who seems to belong in another world, as well. Her best friend, Wendy, is a foster child, who may be taken from her, and her brothers, who are a constant source of loving annoyance. It's a lot of work for an eleven year old, but it's up to her to learn how to bring these two worlds together, all the while discovering the incredible child she'll become.