I am not related, but:
Go to this website and you will see your grandfather's birth record:http://files.usgwarchives.net/tx/cameron/vitals/births/1930/camagb30.txt
Alfredo Alanis, born Nov 13, 1930, Cameron Co TX (Brownsville), son of Belisario Alanis and Josefina Zepeda
Irene G. Zepeda, born June 28, 1886, Texas; died 10-20-1959, Brownsville, Cameron, TX; lived 847 Harrison St, Brownsville. Parents: Felix Garza and Nasaria Zuniga. Informant Luis Zepeda; buried City Cemetery.
Another website to go to is pilotfamilysearch.com, click on search/browse, then click on the US, then scroll down to Texas (there are some Mexican records there too which may help you too).Pick the records you want, input a name for the search and it will pop up the death certificate or whatever information they have:
Belizario Alanis, born Dec 18, 1899, TX; son of Dario B. Alanis (born Mexico) and Maximilana Saenz (born Mexico); died Jan 6, 1955, Brownsville, Cameron Co TX; buried City Cemetery.
1930 census: Brownsville, Cameron, TX: 753 Van Buren St.
307-323: Belisario Alanez, head, 32, married at age 21, TX, TX, TX, waiter in restaurant
Josefina, wife, 29, married at age 18, TX, TX, TX
Belvia or Selivia, dau, 7, TX, TX, TX
Ernesto, son, 5, TX, TX, TX
Irene, dau, 2, TX, TX, TX
Guadalupe, dau, 8/12, TX, TX, TX
Your grandfather would not be listed as the censuses were taken in the first half of the year and Alfredo was nor born until November.
1920 census: Brownsville, Cameron Co TX: Harrison St.
254-257: Irene Zepeda, head, 38, TX, Mexico, Mexico
Josephine Alinis, dau, 19, TX, Mexico, Mexico
Belisario Alinis, son in law, 23, TX, Medico, Mexico
Alfredo Zepeda, son, 18, TX, Mexico, Texas
Belisario Alinis, grandson, 2/12, TX, Mexico, Mexico
1910 census: Brownsville, Cameron Co TX:
468-510: Luis Zepeda, 35, married 1 time, 12 years, TX, TX, TX, servant for City Bank
Irene G., wife, 32, married 1 time, 12 years, 5 children, 4 living, TX, TX, TX
Josefina, dau, 9, TX, TX, TX
Alfredo, son, 8, TX, TX, TX
Luis, son, 2, TX, TX, TX
Begorio?, dau, 2 or 12, TX, TX, TX
Concepcion, brother, 35, TX, TX, TX, no occupation
Also from pilotfamilysearch.org:
Luis Zepeda married Irene Garza, 12 Aug 1898, Cameron Co TX
Trish in TN