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There is an Andrew T Gray, son of William and Ellen M Gray. Later living with William and Magdelena M(ary)/Maggie Gray that appears to be the correct ancestor. Ellen M. must have died because William married 2nd Mary Magdelena Yager. William is the son of Thomas P and Catharine Cahalane Gray from marriage record.. See additional records below.
Indiana, Marriages, 1811-1959
Citing this Record: "Indiana, Marriages, 1811-1959," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/K62Z-ZK2), William C Gray and Mary M Yager, 06 Feb 1906; citing Pulaski County; FHL microfilm 001711319.
Name: William C Gray
Residence Place: , Benton,
White Male Age 31 Farmer
2nd Marriage (Feb. 4, 1894?) Widowed
Birth Date: 15 Mar 1875 Birthplace: Benton, Indiana
Father: Thomas P Gray Birthplace: Lowell, Massachusetts
Mother: Catharine C Cahlon Birthplace: Ireland
Marriage: 06 Feb 1906 Pulaski,
Registration Place: Pulaski, Indiana
Marriage License Date: 05 Feb 1906
Spouse: Mary M Yager (Mary Magdelena on other records)
Residence Place: Indian Creek Twp, ,
White Female Age 27
Birth Date: 24 Dec 1879 Birthplace: Pulaski, Indiana
Father: William Yager Birthplace: New York
Mother: Rosenia Myer Birthplace: Germany
Officiator's Name: Frank X Schalk
U S Census, 1880 Union, Benton, Indiana
Citing this Record: "United States Census, 1880," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MHMD-6FN), T P Gray, Union, Benton, Indiana, United States; citing sheet 272C, NARA microfilm publication T9.
T P Gray Self M 32 MA
Kate Gray Wife F 37 Ire
William C Gray Son M 6 IN
Ellen M Gray Dau F 3 IN
James T Gray Son M 1 IN
Albert Gray Son M 0 IN
U S Census, 1860 Kankakee Townshiip, LaPorte, IN
Citing this Record: "United States Census, 1860," index, FamilySearch (https://familysearch.org/pal:/MM9.1.1/M4N5-QTB), Thomas Grey in household of William Grey, Kankakee Townshiip, LaPorte, Indiana, United States; citing "1860 U.S. Federal Census - Population," Fold3.com; p. 114, household ID 855, NARA microfilm publication M653; FHL microfilm 803275.
William Grey M 50 Ireland
Bridget Grey F 40 Ireland
Patrick Grey M 13 Ireland
Thomas Grey M 12 Mass
Catharine Grey F 9 Mass
William Grey M 10 Mass
James Grey M 4 Mass
Massachusetts, Births and Christenings, 1639-1915
Citing this Record: "Massachusetts, Births and Christenings, 1639-1915," index, FamilySearch (https://familysearch.org/pal:/MM9.1.1/FZS3-WLG ), Thomas Gray, 07 Jul 1847; citing LOWELL,MIDDLESEX,MASSACHUSETTS, ; FHL microfilm 927928.
Name: Thomas Gray Male
Birth: 07 Jul 1847 Birthplace: LOWELL,MIDDLESEX,MASSACHUSETTS
Father: William Gray Mother: Bridget
U S Census, 1900 Jefferson Township, Pulaski, IN
Citing this Record: "United States Census, 1900," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/M9M5-5D3 ), Andrew L Gray in household of William C Gray, Jefferson Township, Pulaski, Indiana, United States; citing sheet 6A, family 27, NARA microfilm publication T623, FHL microfilm 1240399.
William C Gray Head M 25 March 1875 IN married abt 3 yrs
Ellen M Gray Wife F 21 SDec. 1879 IN 2 children 2 living
Andrew T Gray Son M 2 May 1898 IN
Rith R Gray Daughter F 8 mos Sept. 1899 IN
Later census data can be found on familysearch.org