It turned out, the lady was a wealthy widow, somewhat down on her luck. She had been living with her daughter and son-in-law. She was getting senile, and her relatives appeared to have gotten tired of taking care of her; or perhaps they were running out of resources rather than patience. In any event, they took her out to my Grandmother's neighborhood and abandoned her. Nana took her in, and provided her with room and board until this situation could be resolved. The lady had no money (that she had access to), and repaid my family's kindness by giving us some antiques she owned. Which explained why Nana owned some early 19th Century French ceramics.
God Bless your Nana.
She will, or has been, looked kindly upon by the Lord.