Journey to the Crystal Cave (The Adventures of Sophie Mouse, Bk. 12)

Sophie Mouse and her friends are playing hide-and-seek near Butterfly Brook one day. Sophie finds the perfect hiding spot, but she discovers something else, too! It's a cave and it's . . . glowing! The problem is, when Sophie tells her friends about her discovery, they don't believe her! After all, who's ever heard of a glowing cave? Now Sophie is on a mission to prove she's telling the truth!