You're dead if you aim only for kids. Adults are only kids grown up, anyway.
Get a good idea and stay with it. Dog it, and work at it until it's done right.
Suddenly he stops. He looks up. For, lo, there she stands. The girl of his dreams. Who she is or whence she came, he knows not, nor does he care for his heart tells him that here, here is the maid predestined to be his bride.
That's the real trouble with the world, too many people grow up.
A good story can take you on a fantastic journey.
It's kind of fun to do the impossible.