grhita-padah karuno nyavartata
Sukadeva Gosvami said: Rukmini’s utter fear caused her limbs to tremble and her mouth to dry up, while her throat choked up out of sorrow. And in her agitation her golden necklace scattered. She grasped Krsna’s feet, and the Lord, feeling compassionate, desisted.
Srila Visvanatha Cakravarti quotes the “worldly rule” that one’s sister is the personification of mercy: dayaya bhagini murtih. Even though Rukmi was wicked and was opposed to his sister’s best interest, Rukmini was compassionate toward him, and the Lord shared her compassion.