A poet (James Stewart) finds that his 8-year-old son (Billy Mumy) is a whiz at calculations.
I want to tell you something. I don't want you to do it any more. Because if they find out about this, do you know what they're going to say?
They'll say, "There goes that Erasmus Leaf. He's a mathematician."
And we don't want that, do we?
Of course not. 'Course we don't. So... We'll just keep this our own little closely-guarded family secret, huh?