In 1851 she was a widow with three daughters and a mysterious son, possibly Thomas Allen, and an enormous household:

First name(s) Last name Relationship Marital status  Sex  Age  Birth year  Occupation  Birth place
Ann F Dent Head Widow Female 75 1776 Landed Proprietor  Liverpool, Lancashire
Auga Dent Daughter Unmarried Female 45 1806 - London, Middlesex
Susan Dent Daughter Unmarried Female 40 1811 -  London, Middlesex
Haslings Dent Son Unmarried Male 35 1816 - London, Middlesex
A F Max Kinnon Visitor Widow Female 46 1805 Fund Holder  London, Middlesex
Ann Wilkinson Servant Unmarried Female 66 1785  House Keeper  Bernards Heath, Durham
Care Adams Servant Unmarried Female 32 1819 Servant  London, Middlesex
Maria Cophead Servant Unmarried Female 30 1821  Servant  -
Louisa Brand Servant Unmarried Female 25 1826  Servant  Wortham, Suffolk
Helen Hopkins Servant Unmarried Female 22 1829  Servant  Christchurch, Hampshire
Emma Finch Servant Unmarried Female 22 1829 Servant  London, Middlesex
Mary Kemp Servant Unmarried Female 30 1821 Servant  Suffield, Devon
George Tooler Servant Unmarried Male 22 1829 Butler  South Mimms, Middlesex
Charles Manley Servant Married Male 36 1815 Coachman  Scotland
William Oliver Servant Unmarried Male 44 1807 Footman  Croydon, Surrey
Charles Woodrough Servant Unmarried Male 35 1816  Groom  Portsmouth, Hampshire
James Lewis Servant Unmarried Male 25 1826 Groom  London, Middlesex

Address & Ref:
Street Hertford Street
Parish Saint George Hanover Square
City Westminster
County London, Middlesex
Archive reference HO107
Piece number 1476
Folio 275
Page 4
___________________

Their marriage transcription by FamilySearch:

First name(s) John
Last name Dent
Marriage year 1800
Marriage date 29 Oct 1800
Marriage place Huyton by Roby
Spouse's first name(s) Ann Jane
Spouse's last name Williamson
County Lancashire
Country England
Record set England Marriages 1538-1973
_________________

Their marriage licence was from the Faculty Office and dated 11 Oct 1800.
_________________