Curious George, Sheep Herder

At the annual Spring fair in the country, George and Allie come across a sheep shearer and a family making yarn out of a sheep's wool. They also come across a sheep herding contest where Mr. Renkins commands his dog, Bo with a special whistle to herd sheep. When they return home to the country house, the scarf George bought from the yarn makers begins to unravel and they need someone to fix it, but Jumpy Squirrel steals the yarn leaving them in search for more. It seems all of the Renkins' sheep were sheared at the fair and they begin to escape the pasture! George sees the whistle Mr. Renkins used to command Bo and uses it to command Bo to stop the sheep from escaping but is not sure how.