One Summer's Day (1999)

Absent-minded fifth-grader Yuta is sent to spend the summer with his grandfather, whom Yuta's parents think is becoming senile and could benefit from Yuta's companionship. At first, Yuta thinks Gramps is a bit addled, too, but as he gets to know the old man better, he finds that his grandfather sees things quite differently from others.

Is One Summer's Day on Netflix? Unfortunately the movie One Summer's Day is not yet available on Netflix.