canon a musical form where the melody or tune is imitated by individual parts at regular intervals
"Read," demands Sayu.
"Read?" repeats Sachiko, pointing at the nearest picture book. This is how babies learn to speak, apparently, and so Light swallows his indignation at seeing his little sister treated with so little dignity. Anyway, it's not as though she ever seems to notice.
"Yah!" Sayu slaps her hands against her thighs excitedly. "Read! Read Light!"
Light looks up from his own much thicker book on Japanese history. His sister is watching him with big, shining eyes. "You want to read like me?" he translates.
"Yah! Read Light!"
She sounds impatient that he had to ask at all, and Light feels his lips twitch up into a smile. "I'll not stop you," he tells her, and then, to his mother, as he points to a kanji, "What's this one?"
Sachiko glances at the character. "Oh, dear. That's… lottery, I believe. Let's see if I can write it…" As Light watches, committing the stroke order to memory, she draws it on the pad of paper they keep nearby. Most of the top sheet is already covered in increasingly obscure kanji. Sayu looks on, fascinated, her thumb in her mouth.
"I'm nearly sure that's right," Sachiko says, putting down the pen. "Did you see?"
"Uh-huh. Thank you."
"You're welcome, Rai-chan." Sachiko touches his hair affectionately before turning back to her daughter. "Sayu, take your thumb out of your mouth. It's bad for your teeth. Take your thumb out of your mouth, dear."
Sayu blinks innocently.
"Sayu," Light says, "if you take your thumb out of your mouth and let Mom wash your hands, I'll let you borrow my book."
Her eyes go wide with excitement, and she yanks her hand away from her mouth. "Give!" she demands, reaching for the book, but he holds it out of reach.
"Give, what?"
"Give, please!"
But Light just pokes her with his free hand. "Wash your hands."
She pouts, but allows Sachiko to clean her hands with a baby wipe, while Light takes note of the page and paragraph he's reached. Then, true to his word, he closes the book and puts it down in front of Sayu.
"It belongs to someone else, so take very good care of it," Sachiko tells her, but Sayu's clearly not listening. With a triumphant gurgle, she turns the book upside-down, flips it open to the middle, and stares avidly at the lines of text.
Sachiko shoots a look over at Light, who blinks back at her and smiles, before turning back to keep an eye on his book. After a moment, Sachiko shakes her head and does the same.
The glamour of copying Light is clearly paling rapidly, now that Sayu has to actually look at row after row of nonsense squiggles. She frowns, and Light's gaze sharpens. If she's about to start ripping out pages, he'll need to dive in quickly.
But instead, she closes the book with a crisp snap, puts it down, and smiles brightly at her family. "Done!" she declares. "Read big!"
Light raises his eyebrows.
"You did," says Sachiko. "You read a very big book. I'm very proud."
"Read Light," Sayu says with satisfaction.
"Just like Light," Sachiko agrees. "Now–"
Too late to stop her, Light realizes what she's about to say.
"–give him back his book, dear."
Light sighs.
And as Sayu's wailing rises in pitch, he slips out the door, heading toward his bedroom, book in hand. They'll notice he's taken it soon, but not yet.
One way or another, he's learning, he always wins in the end.