I did see a photocopy of the baptism of his daughter for this first marriage. The baptism was recorded in Mexico City. She was actually born in Tampico but the baptism was recorded in Mexico City. I forget what year 154? or 155?
That is part of database where the baptisms and marriages for Mexico City were recorded and indexed. This work was not done by the LDS. I have been waiting for the CD rom to be made available to the public. The researchers spoke only spainish. I saw a demo of the database at a genealogical conference in Corpus Christi. That was one of the records displayed for the conference. They flipped the record up for display. You could see tht the parents were Diego Montemayor and Inez Rodriguez.

As to to the Castano de Sosas being cousins of Luis Carabjal. I don't know. I know of a researcher Art? Bloomer that has done a lot of research on the these lines. His genealogy on www.rootsweb.com show this relationship. I know there are alot ot repeative names between the Carbajals and the Castano de Sosa decendants. Israel Cavazos Garza, historian of Monterrey, has written histories that claimed Diego Rodriguez was the grandson of Diego Montemayor and the son of Baltasar Castano de Sosa and the daughter of Diego Montemayor. That the families came to the new world together can be signifant. Family groups often traveled together. The passenger lists for the voyage to the new world shows these families together. The University of Texas has a copy of the passenger list of the Carbajal voyage that landed at Tampico.

I hope this helps.

Esther