(Most of my learning is via Duolingo, so I'm no expert, just curious.)
It’s losing them fast though. Newer generations just don’t really care, so the words are falling out of use. I really only know cousin, aunt, uncle.
We do have quite a few words in Lithuanian (e.g. for maternal/paternal branches and more detailed words for "X in law"). But it was getting simplified in the past few decades. I've heard quite a few words that I couldn't describe without looking at the dictionary.
On the other hand, it has different words for "wife's mother" and "husband's mother", which in English are both "mother-in-law". Similar for the "father-in-law" relationship: different words for "wife's father" and "husband's father". Similar for sibling-in-law relationships.
(Of course there's the open question of whether Russian would count as "East" or "West".)
* Maternal/paternal parental siblings, with distinct terms for their respective spouses
* Maternal/paternal parental sibling - distinct terms if they are older or younger than your own parent
For aunts its faster/moster (portmanteau of father-sister, mother-sister, roughly). For uncles its farbror/morbror (lit. father-brother, mother-brother).
For grandparents its farfar/morfar (father-father, mother-father) and farmor/mormor (father-mother, mother-mother).
A great grandparent could be e.g. a farfarsfar, or father-fathers-father.
Ours is pretty simple, I imagine this system is intended to cover Chinese kinship which is _really_ complex. https://en.m.wikipedia.org/wiki/Chinese_kinship#Common_exten...