The Penderwicks by Jeanne Birdsall
Don't judge this book by it's cover! These four sisters and their dog are much more fun than the cover would lead you to believe. They are spending their vacation in the cottage on the Arundel estate where they have been warned to stay away from Mrs. Tifton and her garden. So, of course the first thing they do is check out the garden and there they meet Jeffrey, Mrs. Tifton's son who becomes their partner in soccer, bull chasing, rabbit chasing and sadly a bit of garden destruction. If you like adventure, fun, and a family that loves each other very much, but doesn't always get along, read this. Recommended for grades 4 - 6.