This is the 4th book in the "Winnie The Horse Gentler" series by Dandi Daley Mackall. Unlike previous books, this one actually does include a mystery, and the horse Winnie is helping doesn't board in her barn. This time the circus is in town, and she's needing to help a circus horse who is jumpy, frightened, and even disobeying commands he's been taught. But the Russian circus is going to be there to scout for new talent. . . can she figure out what is going on in time?
Sub-plots of the book are Catman's Grandfather "Colonel Coolidge" is in town. He's gearing up for a reunion of army men -- but where are they? Even more important is Winnie's mother's birthday is approaching. Since her mother died, Winnie wants to put on a horse show for the family -- celebrate the birthday like they always did when her mother was alive which meant a movie in the morning, spaghetti for lunch, and a horse show in the afternoon. Winnie wants to teach Nickers to bow because her mother always had her horses bow, but will Nickers learn in time? And besides that, with Winnie's dad headed to the Invention Convention in Chicago, he's not going to be home on her mom's birthday. Lizzie has a writing competition that day, so that leaves -- Winnie -- and Winnie alone to remember her mother's birthday -- or so she thinks!