Where does “свекрвиште” come from?

свекрвиште (Macedonian) comes from Macedonian свекрва, from Proto-Slavic svekry, from Proto-Indo-European sweḱrúh₂, from Proto-Indo-European swéḱuros — father-in-law.

Ancestry of “свекрвиште”, step by step

Step	Language	Word	Meaning
1	Macedonian	свекрва	mother-in-law
2	Proto-Slavic	svekry	woman's mother-in-law
3	Proto-Indo-European	sweḱrúh₂	mother-in-law
4	Proto-Indo-European	swéḱuros	father-in-law

Every word from Proto-Indo-European swéḱuros →Every word from Proto-Indo-European sweḱrúh₂ →Every word from Proto-Slavic svekry →