Code Geass: Lelouch of the Rebellion! Second Resurrection!

Kururugi vi Britannia was the youngest sister of the Royal Family.
Having never met any of her siblings except for Euphemia, she struggles to survive in Britannia until the age of five. Up to the age of five Kururugi only ever met with Euphy.
They played together and had fun until Charles zi Britannia found out and sent Kururugi to the land of Japan to Conquer it.
Kururugi after being saved by a young Milly Ashford enters the brand new school that would become Ashford academy.
Many years later Lelouch and his sister Nunnally are saved by the same Milly Ashford and given a place to stay at the school. Lelouch and Nunnally are given a building attached to the school building to live in.
When Kururugi was rescued by Milly Ashford, Milly thought for some time before giving her the last name Kaname.
So Kururugi vi Britannia grew up as Kururugi Kaname.
All was normal with the school life until a certain incident occurred in the area now called Area 11.
Word was sent to the populace that some Terrorists stole a bio-chemical weapon and were using a stolen truck to transport.

A single individual is sent to find the terrorists and send in word so that a special team can come in and take the bomb. He is an Honorary Britannian or half eleven.

The three's lives would change forever when they encountered each other during the incident.