The 1926-1949 Texas Birth Indexes show at least 8 children for Felipe Santillan & Isabel Lopez.They were all in Harris county between 1927 and ending with a pair of twins in 1941.There could have been more children before 1926. The children names in birth order are Felipe, Velia Jovita, Gloria, Salvador, Lionel Frorentino, Delia, Maria, and Jose who were the twins. There was another Santillan family in Harris county at the time and Augustin Sanitillan might be Felipe's brother.Augustin was married to Carmen Bedolla and their children were Jose Gaspar, Jose Elias, Joe, Teresa, Salvador Bedolla, Ester, and Anna Maria Elena Santillan.
I found these families in the 1920 Harris county Census.
1920 Harris Co., TX Census 5-WD Houston, Clinton Road (All in same household) Santillon Rafael head m w 47 m 1915 Mexico Mexico Mexico Foreman Section work RR " Delores L wife f w 50 m 1915 Mexico Mexico Mexico Santillon Felipe head m w 22 m 1915 Mexico Mexico Mexico Laborer Section hand " Calderon wife f w 18 m 1915 Mexico Mexico Mexico " Esefanio son m w 2 sgl 1915? Mexico Mexico Mexico Santillon Augustin head m w 20 m 1915 Mexico Mexico Mexico Laborer Section hand " Marie wife f 2 18 m 1918 Mexico Mexico Mexico Migel Alford head m w 49 m 1910 Mexico Mexico Mexico Laborer Section hand " Margaita wife f w 50 m 1910 Mexico Mexico Mexico The gender field, w, was marked thru assuming it meant mexican? Appears as if this family migrated in 1915.
Only Augustin was in the 1930 Harris county census.