The ODDS

Hola Members, I have a question concerning my ancestor Toribio Sanchez (marr. to Maria Nieves Martin) .Their Daughter Maria Fermina Sanchez(mestiza) born JULY 14,1822 San Juan de Los Lagos on bautismos 1816-1823 on Image 336. On the bautismo its states Javier Sanchez and Rafaela Lozano as Paternal Grandparents. I went to the familysearch.org IGI (old site) placed the couple mentioned and was given a daughter Maria Petra Sanchez(mulata libre) born Aug.13,1799 Atotonilco el Alto (bautismos 1793-1799,image 386).
The question is ,could the 2 couples -Javier Sanchez and Rafaela Lozano be one in the same ? Is it possible there was a migration from Atotonilco el Alto to the San Juan de Los lagos area ? Another statement Toribio Sanchez and Maria Nieves Martin had another daughter Maria Vicenta Sanchez born July 04,1824 San Juan de los Lagos (bautismos 1823-1829 image 59) and she was classified India. If they are the same couple ,they have a mulata daughter , mestiza and Indian granddaughters from the same parents. Appreciate any incite and I am I missing something ?
Thank you for your time
Ronnie Reynoso