Hi, Renato!
First, a couple of notes about the names:
* Carmen Barcos's birth name is probably Carmen Barco Villalon according to the Spanish naming rules: (baptism name)+(father's first last name)+(mother's first last name) in that order. The "baptism name" could be in fact several names, don't disregard a "María del Carmen" for instance.
* In Francisca's case, the birth name should have been Francisca Perez Martin, not Martin Perez, unless the parents were not married when she was born or the last names were shuffled upon immigration (not uncommon, specially with last names like Martin that can be confused with a first name)
Without knowing the exact town in Málaga or Andalucía (wich are Spanish provinces) where they were born it's not easy to find the baptism records (no civil records in Spain in the 1800') and I'm not very familiar with Spanish sources. I suggest you use the "Images" and "Cataloge" (they don't have the same databases) searching options in FamilySearch instead of the "Records" one, which only looks in the indexed microfilms. I hope this helps a bit.
Good hunt!
