The back of this photo says (in Mildreds hand) Etha and Louise. Etha was a first cousin to Mildred. She lived in Santa Cruz, when I met her in the 1960s. But there is evidence she lived in several other places in the United States. The wonderful photograph of the family at Mildreds birth was a postcard sent to Etha in West Virginia.
Etha would be the mother in this group.