brotherboy-and-sistergirl

Brotherboy and Sistergirl are Aboriginal and Torres Strait Islander terms coined by Australia's First Nations peoples and are exclusive to those peoples. Though Sistagirl and Brothaboy are not terms that are related to Sistergirl and Brotherboy, more used as terms of endearment or sentiment, they can still be used in relation.

Excerpt from AIFS - Glossary of common terms;
Sistergirl/Brotherboy: terms used for gender diverse people within some Aboriginal or Torres Strait Islander communities. Sistergirls and Brotherboys have distinct cultural identities and roles. Sistergirls are Indigenous people who were classified male at birth but live their lives as women, including taking on traditional cultural female practices.
Brotherboys are Indigenous people who were classfied female at birth but live their lives as men, including taking on traditional cultural male practices.

Brotherboy and Sistergirl identity is not exclusive to trans masculine or trans feminine peoples and can also include masculine/feminine nonbinary people, masculine gay women or feminine gay men, and drag kings or queens.

This information may be wrong. Please DM me on Twitter if anything needs to be changed.