Twins - Book 15: Mixed Emotions>Normally, the campers would be relieved to be rid of the troublesome girl, but this situation is serious. Added to that problem is the fact that Liam, Ethan, and a few other kids have disappeared as well. Will they all return safely or will the worst imaginable scenario take place? And what about Casey and Ali? Are they finally able to restore their relationship as sisters, or will the summer destroy their friendship forever? Mixed Emotions is another great book for girls 9 -12 that all fans of the Twins series are sure to enjoy.