An old man of 70 married a young wife, and his wife got pregnant. The old man found a doctor: My wife is pregnant, am I great?

Doctor: Let me tell you a story, there was a hunter hunting in the mountains, his gun was out of bullets, but he encountered a bear. He had no choice but to raise an umbrella, unexpectedly the bear fell to the ground. Why?

Old man: That must be because someone else was shooting.

Doctor: That must not have been his bullet.

The question arises, whose bullet was used by the smart king?