Boo and Baa Have Company by Lena and Olof Landstrom. 

If you have not read the earlier Boo and Baa books, run out and get them.  Boo and Baa are two quirky little sheep who have small adventures that are filled with humorous moments.  In this story, Boo and Baa are raking the leaves in the lawn when they hear a meowing noise.  It takes them awhile to locate a cat caught in the tree above them, although children will immediately know what is going on.  Then comes the rescue of the cat, leading to lots of laughter-inducing action.  It is a lot of fun. 

Landstrom’s use of spare language underpins all of the humor and the simple illustrations carry the story with one or two lines adding tension to the pictures.  The illustrations may be simple but they are masterfully so.  Boo and Baa will appeal to preschoolers, but even older children will enjoy the humor here.