ભાભી હસવું ભુંડું.

bhābhī hasavuṁ bhuṁḍuṁ.

Literally: A sister-in-law's laughter is bad.
What it means: Mockery or teasing from close female relatives can be highly hurtful and cause family discord.

Also said as

ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1923) ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1921) · read from the scan by machine — the Gujarati itself is unchecked · English is machine-made and nobody has checked it yet

Heard it differently, or know we've got the sense wrong? Tell us — that is exactly the kind of correction this needs.