It's not a class, it's a variable. The Or is there because the same Chinese word refers to two possible relationships within a family tree. It doesn't do more t

It's not a class, it's a variable. The Or is there because the same Chinese word refers to two possible relationships within a family tree. It doesn't do more than one thing, it represents more than one relationship. If the word 'Sibling' didn't exist, we could use 'BrotherOrSister' in its place.