by Diana Wynne Jones.

This is another fantastic YA by DWJ about a girl who has done nothing but read books her entire life and has become thoroughly useless.  My mother may find this singularly appropriate; however, it’s the mother’s fault for forcing this uselessness (as a pretense to “respectability”), so watch it.

The girl, Charmain, has to watch her uncle’s house while her uncle undergoes magical treatment to cure a mysterious disease.  Meanwhile, the uncle, who is a wizard, and thus (to Charmain’s mother’s mind) disrespectable, has left his magical house in a shambles.  Charmain, the wizard’s brand-spanking-new apprentice, and the wizard’s adopted stray dog get dragged into the effort by Sophie (secretly accompanied by Howl) to save the kingdom.  She learns how to work magic, do the laundry, and save the kingdom.  Huzzah!

SPOILER:

Howl shows up in this one as a spoiled, lithping brat named Twinkle, which is worth the price of admission right there.  I heard this on audiobook, read by Jenny Sterlin, while at work and had to repress laughter to prevent people from asking what I was laughing about, and thus, interrupt the story.