Seeds in My Head

I was playing basketball with my children the other day (daycare children), and one of them was upset because he could not make the ball go in the basket. I sat him down and told him that very soon he would be tall enough and he would be able to make it in all by himself. That seemed to please him. He went and played on some other toys, but I noticed he kept rubbing the top of his head. I asked him what he was doing, was he OK? He said he was feeling for seeds. I said, "What do you mean?" His reply: "I have to have seeds in my head if I'm going to grow."