From familysearch.org Maria Ysabel de Jesus d/Romolo Sanchez & Mariana Jimenez Bap 30 Nov 1892 Santa Ana, Guanajuto, Mx
Maria Estefana Bap 08 Sept 1895 San Nicholas del Monte, Guanajuato, Mx
I also found a border crossing record for Florentino Sanchez, accompanied by father, Romolo Sanchez. A second border crossing record with little information except that it had Florentino's place of birth as San Felipe, Guanajuto, MX. Of course, it could be a different Florentino Sanchez but you have to start looking somewhere.
You can go to the link above to view digital images of baptism reoords. First page scroll down to -Browse by Location and click on USA,. Canada & Mexico. Next page: Scroll down aphabetically to Mexico and click on Guanajuato Church Records. Next page: Click on Browse through records. Next page: click on Guanajuto, Next page: click on San Nicholas del Monte, or Santa Ana, or San Felipe --start wherever. Next page: select baptims records, years you want to research--You will see on the top bar-- Total images- You can jump pages forward by entering a number into the square before Total Images. You may be able to find Florentino's baptim record at one of those places. You may be able to find his father's marriage record too.