This has come up in the past. I believe Mandarin has a short and quick word for this. English doesn't have the same cultural background so there's no quick name for it.
Compare this to writing out "MothersOrFathersBrotherOrSistersDaughterOrSon" instead of "cousin". In fact, my own language doesn't even have a word for "sibling", all we have is "brother or sister", despite being surrounded by languages that do have such a word.