History has a lot to say about transgender children. We have always existed and no amount of harassment or discrimination by politicians, religious leaders, teachers, or parents changes that. Yes, it is damaging. But history shows that for hundreds of years, young people have persisted in transing gender in the face of incredible hostility. Some resources:

Stories of trans kids from 19th century American literature

Stories of female husbands (most transed gender as teenagers) from 18th & 19th century U.K. and U.S. newspapers

Brilliant history of trans kids by Jules Gill-Peterson