Also don’t chinese family relationships distinguish beetween maternal and paternal-side relationships? E.g. a cousin on your father’s side is called / qualified / described differently than a cousin on your mother’s side?
As I understand, only children of father's brothers can be prefixed with 堂, because they have the same last name and are traditionally considered to be in the same house. All others, including children of father's sisters, are all prefixed with 表.
堂哥 male cousin older than me 堂弟 male cousin younger than me 堂姐 female cousin older than me 堂妹 female cousin younger than me
表哥 male cousin older than me 表弟 male cousin younger than me 表姐 female cousin older than me 表妹 female cousin younger than me