While I was searching about cows in the Vedas and Grihya sutras, I came across a mantra from Vajasaneyi Samhita of Shukla Yajurveda. This mantra is chanted by the bridegroom during the madhuparka ceremony in marriages.
I say this to Rudra's mother, to the Vasu's daughter, to Aditya's sister, to the navel of immortality- to the one who understands: Do not kill the innocent cow, the Aditi, the knower of the speech who raises her voice.... Let loose the cow. Don’t kill this cow for me release her, let her drink water and eat grass!" - (And) gives order (to the people), 'Om! Let it loose
Hiranya Keshin Grihya sutras I prashna, 4 Patala Section 13
This is talking about Madhuparka ceremony where the guests are offered meat and then he refuses. In these mantras, there is a mention of Rudra's mother, Vasu's daughter, Aditya's sister and the navel of immortality. Who are these? Is it a reference to a single person or different persons talked about here?
I couldn't find a detailed translation and explanation of these mantras. I could only find that these are examples of mercy and sanctity towards cows by naming them as Goddess in the Vedas and other scriptures. What is the complete meaning of the mantras and complete context these mantras were heard by the rishis?