chhin-ke親家

one's child's parents-in-law

one's child's parents-in-law; co-parents-in-law

more broadlyparticularly

English Wiktionary, “親家” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E8%A6%AA%E5%AE%B6 · confidence: Medium (Wiktionary PH)