Grandmother Mary Montano in whose house the incident takes place, mother Corrina Vargas, 26, son Carlos Mendez, 10. Nobody has the same last name.
-PJ
Married women in Hispanic cultures typically keep their own name and add "de" plus the husband's name. So Grandma might be named Mary Montano de Vargas, while Mom might be Corrina Vargas de Mendez.
Or not.
-ccm