It has been some time since I worked on this line, but I do have very large files. I do not know is a large file is appropriate to copy to a thread. Here is what I have on the Tew line.
Mary Ann Malsbury

Mary Ann Malsbury is found in the 1861 census recorded as the niece of John Tew.
I have attempted to verify this. Mary Ann’s mother was Mary Walker and, in turn, her grandfather was William Walker.
The name Walker is the only common connection I can find. Catherine Walker was the mother of John Tew and likely the great aunt of Mary Ann. William & Catherine were likely brother & sister.
I have included in my findings, the likely Walker Tew connection. This has not been verified, but I believe it to be correct.

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Aug. 4, 1808 Marriage Richard Tew & Catharine Walker Woodford Halco, Northants.
ref. Northamptonshire Marriages

1851 Census. Address: Woodford Village, Woodford, Daventry, Northamptonshire.
The household -
Richard Walker Tew age 31 (b. 1820) Woodford, Northamtonshire
Farmer of 187 acres 6 Labs. & 6 boys
Ann Tew age 35 (b. 1816) Adstone, Northants.
John Tew age 32 (b. 1829) Underwood, Northants
Farmer in partnership with his brother
Elizabeth Tew age 2 (b. 1849) Woodford, Northants.

1853 Q2 Marriage John Tew & Sarah Whitmell Perridge Towcester, Northants. 3b 39
ref. Northamptonshire Marriages

July 7, 1814 Marriage Robert Perridge & Elizabeth Whitmell Crick, Northants.
ref. Northamptonshire Marriages

Dec. 10, 1822 Baptism Sarah Whitmell, dau. of Robert & Elizabeth Perridge
Maidford, Northants. ref. Northamptonshire Births & Baptisms

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1861 Census. Address: Town Street, West Haddon, Daventry, Northamptonshire.
The household –
John Tew age 32 (b. 1829) Underwood, Northants.
Farmer of 248 acres employing 8 men & 5 boys.
Sarah Whitmell Tew age 39 (b. 1822) Adstone, Northants.
Eliza Tew age 7 (b. 1854) Crick, Northants.
Mary Elizabeth Tew age 5 (b. 1856) West Haddon, Northants.
John Tew age 4 (b. 1857) West Haddon, Northants.
Elizabeth Fernandez Tew age 2 (b. 1859) West Haddon, Northants.
Mary Ann Malsbury age 20 (b. 1841) Daventry, Northants. Niece Unmarried
Retired farmer’s daughter

1871 Census. Address: West Haddon, Daventry, Northamptonshire.
The household –
Mary Ann Folwell age 79 (b. 1792) Pattishall, Northants. Interest of money Single
Mary Ann Malsbury age 30 (b. 1841) Daventry, Northants. House Keeper Niece Single

1881 Census. Address: West Haddon, Daventry, Northamptonshire.
The household –
Mary A. Folwell age 87 (b. 1794) Pattishall, Northants. Living Independent Single
Mary A. Malsbury age 40 (b. 1841) Daventry, Northants. Attendant upon aunt Niece Single

1891 Census. Mary Ann is at the home of her sister and brother-in-law, Eliza & William Hunt.

1898 Q1 Death Mary Ann Malsbury age 57 Aston, War. 6d 231

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