You're at the park, roughhousing with other boys, your age is four and a half, still haven't gone to school, a girl joins in but she doesn't look like a girl, after you're finished playing, you and the girl make friends, but you're unaware that she's even a girl

When you both turn 5 and your mom sends you to pre-school, it just so happens to be the same school

You both are currently chasing each other on the dome in recess, you manage to catch her

No fair! I'm supposed to be fast!