From the moment his son was born Shikaku knew with a father's intuition that Shikamaru was smart. He knew it for a fact when he saw how early the boy figured out that his father would easily break under constant tears, but his mother would not. Shikaku knew deep down his son was a genius, as he watched his son outgrow his toys and not even blink at the mysterious alphabet. When the boy stopped flinching under his mother's rage, and especially when he started talking.
But he never thought his son's genius would bloom so early. He could see it now, as he read Shikamaru the same fairytale his father had read to him. He could see it behind his son's eyes, could see him start to question the possibilities and probabilities of the story.
Shikaku did not know how much longer he could keep reading to his son like this; like he was a child and believe every word his father said. But he would, as long as Shikamaru would let him.