Phil, You didn't give any approximate dates of births or marriages but this seems to fit your family.
1900 U.S. Census J-P 4 Presidio TX Tomas Madrid Head, age 35, Head, married, Alien/Imm 1915 Felicia wife, age 40, married, Alien/Immigrated 1915 name unreadable19 single, Al/1915 Alberto son 17 Al/1915 Amanda daughter 15 Al/1915 Diego son 14, Al1915 tomas son 8 AL/1915 Luz daughter 7 Al/1915 Carmen born in Tx
Next family listed in this census: Baeza Demetra head, widow Al/1915 Ascension daughter 31 singleAl/1915 Guillermo 28 single" Angel son, 20 single" Secundina niece 17
1930 U.S. Census Precinct 5 Jct, Shafter, Presidio, TX Tomas Madrid head, 58 married at age 27 Al/1910 Felicia wife, 51, married age 20 Al/1915 Amanda daughter 29, singel born MX Al/1910 Tomas Jr 21 born in Mx Al/1910 Luz daughter 18 born in Texas Carmen daughter 16 born in Texas.
There was another Tomas Madrid living in the same town in 1920 whose wife was Dorotea. They also had a son named Tomas but I don't think that's the right one because I this other record. From the Family History Library-Family Search: Tomas Madrid married Felisa Baeza 08 Jan 1898 Jesus Nazareno Ojinaga, Chihuahua, MX Tomas Madrid: Father-Andres Madrid Mother: Felisita Valenzuela Felisa Baeza: Father-Diego Baeza Mother- Demetria Vazquez
Andres Madrid married Felicitas Balenzuela 07 Jan 1868 Jesus Nazareno Ojinaga, Chi, MX Andres Madrid: Father- Olayo Madrid Josefa Madrid
My suggestions are the following: Order a copy of the death certificates for those you have a date of death.You never know what info may be in it. For those who had social security cards, order a copy of the original social security application. It usually has the applications parents names.
Call your local library/genealogy library and ask if they Ancestry.com access for their patrons. If they do, check out the Border Crossing Records-Mexico. You may or may not find your relatives. I can't remember what year the records begin. Also check the WWI Registration records on Ancestry.com. Try the names of brothers. Also, you can write to NARA and ask for a search of Alien Registration Records for Tomas Jr. You won't be charged until NARA finds a registration record. If you are interested in checking that out, let me know and I'll send you the link.