Birthdate uses death date on tombstone and calculated backward 75y 3m 1d. (may not be correct) *See baptism

Scotland, Select Births and Baptisms, 1564-1950
Name: William Biggar
Gender: Male
Baptism Date: 21 Dec 1799
Baptism Place: Lilliesleaf, Roxburgh, Scotland
Father: Thomas Biggar

1851 Census of Canada East, Canada West, New Brunswick, and Nova Scotia
Name: William Biggar
Age Next Birthday: 52
Estimated Birth Year: abt 1799
Birthplace: Scotland
Census Year: 1851
Enumeration District: Beauharnois County
Sub-Enumeration District: Godmanchester
Residence Place: Beauharnois, Canada East (Quebec), Canada
James Biggar 61 and Jennet Murry 50
James Biggar 27
Elizabeth Biggar 22
David Biggar 17
Jennet Biggar 16
Robert Biggar 13
Margaret Biggar 10
William Biggar 52 and Elizabeth Addams 48
William Simpson 24
Margaret Biggar 17
Thomas Biggar 15
Anne Biggar 15
Martin Biggar 11
Mary Biggar 9

Iowa, State Census Collection, 1836-1925
Census Date: 1856
Residence State: Iowa; County: Chickasaw; Locality: Bradford
Household Members:
Wm Biggar (55) and Elizabeth Biggar (50) wife
James Biggar 19
Anna Biggar 17
Martin A Biggar 14
Mary Jane Biggar 12
Elizabeth Biggar 9

1860 United States Federal Census
Birth Year: abt 1801 in Scotland
Home in 1860: Bradford, Chickasaw, Iowa
Occupation: Farmer
Household Mebers:
William Bigger 59 and Elizabeth Bigger 55
Martin Bigger 19
Mary Jane Bigger 17
Elizabeth Bigger 15

Source: Ancestry.com Family Trees (accuracy not guaranteed)
Name: William Biggar
Birth: 1799 in Scotland
Death: 1876 in Iowa
Father: Thomas Biggar (1761–1820)
Mother: Ann Mitchell (1761–1843)
Spouse: Elizabeth Adams (1806-1864)
Children:
James (1826-1872)
Margaret A. (1835-1927)
Thomas (1837-1920)
Anne (abt. 1838-____)
Martin Adams (1841-1902)
Mary Jane (1843-1940)
Elizabeth (abt. 1844-____)