This confusion has resulted in Vietnamese people unintentionally describing incest or gay relationships.
[0] - What she actually meant was "brother" in the sense that he is a family friend and neighbor.
It's a miserable experience for translation software.
Basically what OP is saying is interpersonal relations can be confused when using the Vietnamese and English definitions of both words.
Anh and Em essentially means masculine and feminine, but is also often used in romantic, non-romantic, casual, and sometimes formal usecases and this is heavily dependent on the verbs and adjectives that follow.
Viet-English NMT is very flawed at the moment.