Agrelon

HasRelative

https://d-nb.info/standards/elementset/agrelon#HasRelative
Has subclass: has cousin, [...], has sibling

could be combined as sibling could be seen as zero grade cousin

HasInlaw

https://d-nb.info/standards/elementset/agrelon#HasInlaw
Label (German)	hat angeheiratete(n) Verwandte(n)
Has subclass: has fiancee or fiance

false, as "fiancee or fiance" (Verlobt) is not a subclass of "angeheiratet"