In 1851 he was a widower with a nephew with his wife and their two sons and four daughters at Rise, Skirlaugh, Yorkshire:

First name(s)  Last name  Relationship  Marital status  Sex  Age  Birth year  Occupation  Birth place
Richard          Bethell      Head      Widower    Male    78  1773  Landowner Magistrate    Middlesex
William Froggat  Bethell      Nephew    Married    Male    41 1810  Gentleman & Magistrate  Ely, Buckinghamshire
Elizabeth        Bethell      Niece     Married    Female  30  1821  Mr William Bethell's Wife  Doncaster, Yorkshire
Maria            Bethell      Daughter  Unmarried  Female   9  1842  -                          Rise, Yorkshire
Lucy             Bethell      Daughter  Unmarried  Female   6  1845  Children Of                Doncaster, Yorkshire
Charlotte        Bethell      Daughter  Unmarried  Female   5  1846  Mr William Bethell         Rise, Yorkshire
William          Bethell      Son       Unmarried  Male     3  1848  -                          Rise, Yorkshire
George           Bethell      Son       Unmarried  Male     2  1849  -                          Rise, Yorkshire
Elizabeth        Bethell      Daughter  Unmarried  Female    0  1851  -                          Rise, Yorkshire
Mary             Buckingham   Servant   Unmarried  Female  33  1818  Governess                  Merton, Surrey
Elizabeth        Hammond      Servant   Widow      Female  38  1813  Housekeeper                Copgrove, Yorkshire
Maria Louisa     Bergut       Servant   Unmarried  Female  30  1821  Lady's Maid                France
Rebecca          Travis       Servant   Unmarried  Female  30  1821  Nursery Maid               Yorkshire
Mary             Spright      Servant   Unmarried  Female  17  1834  Nursery Maid               Yorkshire
Jane             Tasker       Servant   Unmarried  Female  33  1818  Cook                       Yorkshire
Mary             Lambert      Servant   Unmarried  Female  22  1829  Still Room Maid            Appleton, Yorkshire
Mary             Stubbs       Servant   Unmarried  Female  30  1821  Laundress                  Harewood, Yorkshire
Ann              Wilkinson    Servant   Unmarried  Female  29  1822  Housemaid                  Wadworth, Yorkshire
Ann              Etherington  Servant   Unmarried  Female  21  1830  Laundry Maid               -
Harriet          Hardy        Servant   Unmarried  Female  18  1833  Kitchen Maid               Seaton, Yorkshire
Eliza            Underwood    Servant   Unmarried  Female  21  1830  Scullery Maid              Melton, Yorkshire
Hannah           Underwood    Servant   Unmarried  Female  26  1825  Housemaid                  Melton, Yorkshire
Mary Ann         Proctor      Servant   Unmarried  Female   23  1828  Dairymaid                  Yorkshire, England
Mary Jane        Harker       Servant   Unmarried  Female  16  1835  Housemaid                  Swine, Yorkshire
Sarah            Penrose      Servant   Unmarried  Female  20  1831  Nurserymaid                Melton, Yorkshire
John             Robinson     Servant   Unmarried  Male    71  1780  Butler                     Whitwell, Yorkshire
Thomas           Harrison     Servant   Unmarried  Male    33  1818  Groom                      Yorkshire
Jonathan         Duggleby     Servant   Unmarried  Male    25  1826  Under Butler               Yorkshire
Robert           Chipchase    Servant   Unmarried  Male    27  1824  Footman                 Danby Wiske, Yorkshire
Charles          Day          Servant   Unmarried  Male    16  1835  Footman                 Sigglesthorne, Yorkshire
Bently           Parker       Servant   Unmarried  Male    26  1825  Groom                   Yorkshire
George           Rudd         Servant   Unmarried  Male    20  1831  Footman                 Rise, Yorkshire
Thomas           Prescott     Servant   Unmarried  Male    30  1821  Coachman                -

Ref:
Archive reference HO107
Piece number 2365
Folio 122
Page 11
Combined            HO107, piece 2365, folio 122, p. 11

I suspect that he had invited his nephew to join them and inherit his estate.  Note that the nephew’s children were mostly born at Rise.  The conclusion is that he and mary might not have had any children.

In 1861 his nephew and children were still with him.

With the large income to support this styple, I wonder if his family was in Burke’s Landed gents?  Yes he was!
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In Burke’s LG of 1871, vol 1, p. 93, there is:

Richard Bethell, Esq. of Rise and Walton Abbey, co. York, late MP for the E.R., b. 10 May 1772; m. 26 April 1800, Mary, 2nd dau. of William Wellbank [sic], Esq. of the city of London. Mr Bethell s. to the estates under the will of the late Williamd Bethell, Esq.  He d.s.p. 25 Dec 1864, and was s. by his nephew, the present William Bethell, Esq.
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His burial transcript:

First name(s)      Richard
Last name          Bethell
Age                92
Birth year         1773
Death year         1865
Burial year        1865
Burial date        02 Jan 1865
Burial place       Rise
County             Yorkshire (East Riding)
Country            England
Archive            East Riding Archives & Local Studies Service
Archive reference  E-PE80-9
Page               23
Record set         Yorkshire Burials
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