You were Nico's older sister.

But... You were very, very short. (Bear with me, guys, I'm expressing my pain of being shorter than Hazel)

One day, y'all were just hanging out, Nico chatting cough hopelessly flirting cough with Will. You were just talking to Piper about something, while Annabeth had left the conversation to make sure Percy and Leo weren't dancing around in sharkie outfits again (don't ask).

It was getting pretty late, and Nico was tired, so he said goodbye to Will and said that him and his little sister were heading back to the Hades cabin. That didn't make sense, Hazel was at Camp Jupiter... Oh, yeah, he meant you.

As you are walking back, you bring it up.

"But I'm older than you?" You said, and he immediately knew what you meant.

"But you're shorter." He retorted.