The Tiger Rising by Kate DiCamillo

"Walking through the misty Florida woods one morning, twelve-year-old Rob Horton is stunned to encounter a tiger -- a real-life, very large tiger -- pacing back and forth in a cage. What's more, on the same extraordinary day, he meets Sistine Bailey, a girl who shows her feelings as readily as Rob hides his. As they learn to trust each other, and ultimately, to be friends, Rob and Sistine prove that some things -- like memories, and heartaches, and tigers -- can't be locked up forever."--Résumé de l'éditeur.