Mary Eleanor Scully (Rozells) - Re Mary Eleanor Scully's possible parents and siblings

I wonder if Mary Eleanor Scully (nee Rozells) could be the daughter of Jeromina Peterson and Wenceslaus Rozells, and the sister of my paternal great grandmother Elizabeth Myler (nee Rozells). Notes on the back of this photo identify the woman in the foreground as "Mary Scully older sister of Elizabeth Myler".