The Reasons i will tell you listen
Goddess Parvati is herself Bhavani for the following reasons:
BHAVANI means
Sanskrit Root Breakdown
Bhava (भव): Means "existence," "being," or "source." It is also a name for Lord Shiva.
Ani (आनी): Means "she who brings" or "the source of."
further it also means :
The Consort Connection: Bhavani directly translates to "the wife of Bhava (Shiva)"—identifying Goddess Parvati/Durga as the divine partner of Lord Shiva.
There after it also means :
The Life-Giver: Together, they show that Shiva is the underlying reality of the universe, and Bhavani is the active, nurturing power that breathes life and form into it.