Books with title William and the Moon Rocket

This is the first book in the series about a five year old boy named Willie who has the most incredible things happening in his life. He discovered one evening that If you watch the moon on a dark night when it is full, you will find that it will follow you where ever you go. It is always there calmly. serenely accompanying you, no matter how you may try to leave it behind. And if you stop, just for a moment, how quickly you can become entranced and bewitched by the light streaming down to greet you.