I imagine the blank drawings as completely blank double page spreads in a published picture book some day, but if that's too much for a publisher, I suppose the boy could simply be portrayed holding up a blank sheet of drawing paper.
Here's an excerpt from the completed 464 word first draft:
“Give me one more!” said Freddie.But wait, you're probably thinking now. I thought every picture he draws is just a blank sheet of paper. What happens to this picture he's drawing right now?
“Okay,” said his father. “But this one’s going to be an easy one. Draw me a picture of everyone who loves you.”
That one turned out to be harder than it sounded!
At first, Freddie drew a picture of his family, but that wasn’t everybody who loved him. So he added his teachers, and then his friends, and then he thought, “I wonder if my doctor loves me, too?”
His picture got bigger and bigger, until finally he was finished and he brought it to his father.
You'll have to read the published picture book someday (and hope it gets published in the first place) to find out!