एष ते रुद्र भाग: सह *स्वस्त्राम्बिकया* तं जुषस्व स्वाहैष ते रुद्र भाग S आखुस्ते पशु:।।57।। Rudra, this is thine allotted portion. With *Ambika thy sister* kindly take it. This, Rudra, is thy share, the rat thy victim. (Shukla Yajurveda 3.57) Why is ambika devi being called rudras sister?