not all of the children may be her children. Could be James and Adeline belong to Nancy

If this is the person listed in 1900 census as a widow age 75, she had a daughter Tabitha. But Tabitha may belong in a totally different family, but mother Mary’s birthdate is close (1822, 1825)

Beside the name of Mary, mother of Tabitha, 1900 census has 1 total and 1 living child in 1900. This fits for Tabitha, but not for this Mary. Nothing beside name of Tabitha, despite listing of son, John!

Oakley (b 1861) is definitely one of the children, his parents are listed in his marriage record2

1910 census shows a Mary Blake, widowed, age 78 with daughter, Martha Ewell (b ca 1855), and grandson, Joseph Selby (b ca 1896)133