Linnets and Valerians, Elizabeth Goudge.
"Robert gave the box-room door a resounding kick, merely for his own satisfaction, for he knew that only the kick of a giant would have made any impression on its strong oak panels, and sat down cross-legged on the floor to consider the situation. Betsy was roaring in the bathroom, Timothy was yelling in the broom cupboard, Nan was sobbing in the linen room, and Absalom was barking his head off in the small cupboard where the boots were kept." (p. 1)
Who can resist a beginning like this one?
The resourceful and "high-spirited" (as their father calls them) Linnet children are left to live with Grandmama while their father rejoins his regiment in India. After the incident which leads them to be locked away, they escape, hop into a pony trap that's been left awaiting its driver outside an inn, and conveniently land at the home of gruff Uncle Ambrose, a vicar and retired schoolmaster who has said that he hopes never to set eyes on a child again. Naturally, the children have a smashing magical adventure in the woods and hills, foiling the spells and wickedness of a witch and reuniting a lost family. This is a delightful story. I remember curling up on the arm of the faded stuffed rocking chair when my mother read it out loud, and it was just as delightful to read it aloud to the fine young gents.