I find the moral of the story problematic. Allegedly, we should learn from the mouse the virtue of patience. However, in practice, we see the four other animals collaborating in a creative effort to achieve a goal - get the apple. They attempt, and fail, and never give up, and eventually they figure out a way that almost works, and everyone joins in and nearly achieve their goal. Everyone - except the mouse! Which makes no effort, does not join in to assist his friends, just waits there passively in its confidence that the world will provide for it his shiny apple. Having this behavior rewarded and praised makes this book a seriously flawed one in my opinion.
Mouse is waiting patiently under the apple tree, watching for a single red apple to fall. As other animals wander by, they each decide to wait, but less patiently. Each of the animals try to get the apple to fall, unsuccessfully, but they give up and leave. It must have been bad anyway, the others say as they wander away. But still, the mouse waits. This is an excellent take on the phrase "Good things come to those who wait," and learning about patience.