Yiddish: A black cat has run between them.

Their relationship has soured.  SOURCE: Stutchkoff, Der Oytser fun der Yidisher Shprakh.

‏‏עס איז דורכגעלאָפֿן צווישן זיי אַ שוואַרצע קאַץ.

Es iz durkhgelofn tsvishn zey a shvartse kats.

A black cat has run between them.