I, unfortunately, have very little info on Romos in the 1800s. However, I did look up Catarino Romo in the LDS FamilySearch program and found some interesting info. I've decided to post it here in the case it may be of use to anyone else.
THE GOOD NEWS.....
I did find an additional child for the marriage you described (Catarino Romo & Dolores Garza):
Dominga Romo Garza - c. 9 Aug 1868, Rincon de Romos, Aguas.
(Film #0635640, Batch K603833)
THE PERPLEXING NEWS
Catarino's marriage to Dolores has not been extracted and does not appear in the database, but another marriage of interest does:
Catarino Romo m. Petra Aranda.....24 August 1876....Rincon de Romos, Aguas. (Film #0635734, Batch #M603841)
Initially, I thought this might be a 2nd marriage for him - since none of his children would be of marrying age in 1876. Petra Aranda may be related to Catarino's son-in-law's family.
Later I realized that this may also be the 2nd marriage for another Catarino Romo of Rincon de Romos. It appears that there were 2 by this name, about the same age, in this town at the same time. Specifically, I found:
Catarino Romo m. Telesfora Velasquez
This couple had 3 children:
Policarpio - b. 22 Jan 1862, Rincon de Romos
Luisa - c. 25 Aug. 1864, Rincon de Romos
Florentina - c. 17 Mar. 1868, Rincon de Romos
But...THIS IS THE ONLY FLORENTINA THAT APPEARED IN THE DATABASE. It seems coincidental that a man by the same name, near the same time period, had a child by the same name as the one you are researching. Could these be related?
To complicate things even further, I'll add the following:
Catarino Romo m. Dolores Lara
26 June 1867, San Luis Potosi, SLP (Film #640837)
and their daughter,
Eulogia - 12 Mar 1870 - Tlaxcalilla, San Miguelito, SLP
One thought....the surname Garza does appear extensively through TX, Coahuila, Nuevo Leon, Tamaulipas and SLP. Could these people be related??
Well, hope this helps more than it perplexes. Let me know if you have other questions. Regarding the extractions - they are not for sale, as I've not even finished compiling the families and none of it's computerized, but I'd be happy to help you with look-ups. Before too long, I hope, the family compilations and loose extractions will be available for purchase.