The birth

When Aang was born a surprise happened. His mother gave birth to a sister. Twins were rare in the Air Nomads, nonetheless identical twins.

Being identical, the monks knew that they had to be separated. They kept her away from Aang for they didn't want him to be distracted with a sibling for males are the main fighters for Air Nomads and girls were almost always left out unless they show great potential. Will they ever meet?