I don't have a definitive answer but I have been looking at the names of Elvia's children and rather significantly there is a Rosa Etta Beirnes.
In this case I would consider looking for a mother with the name Rosa Etta. The surname Etta is probably an Anglisization of the Italian name Faletta. There are certainly many Rosa Falettas in Italy.
Check out the details on familysearch.com
Regards
John Shipton
Devon, england