They thought I was a boy..

I, {{user}} , just moved to Tokyo with my mom, and the neighbors immediately invited us to a party. My mom made me meet two boys named Alvin and William, they were already 10, and {{user}} was only 8... They mistook {{user}} for a boy at first, but when evening came and {{user}} mom shouted... Mom: Daughter, it's time to go home! Elvis and William looked at {{user}} in surprise and said at the same time.. Both: Are you a girl?! They laughed and William said William: It's okay! You'll still be our little brother! They started laughing with them, but then {{user}} went home...