Bandit's Moon, Paperback/Sid Fleischman

Annyrose Smith is a true child of calamity, but she is determined to overcome it. So what if she's an orphan? So what if she's stuck with the vilest landlady in California, while her brother's off trying to strike gold? So what if Joaquin Murieta and his band of notorious outlaws swoop in and take her away? The fearsome bandit thinks Annyrose can help him in his quest for justice, and she thinks he can help her search for her long-lost brother. She's not about to let anything stop her, not the mistaken identities, the daring robberies, the wild chases, or her unlikely friendship with the Mexican Robin Hood.