Not sure if you have seen it but I found the Civil Registration of Frumecios birth. It mentions that he is a “Hijo Natural” of hers and Francisco, both from Cerritos. What this means is that Victoriana and Francisco were not married. Either they married later on or never married. I guess time will tell as more indexing is done for Mexico. Here is the link to the birth record: https://familysearch.org/ark:/61903/3:1:3QS7-L9V2-9GKR?cc=1916237