I believe this is the family in 1841
District 22, Upper & Lower Llangerniew
Marchaled, Llangernieu, Denbighshire
Robert Jones, 70
Elinor Jones, 65
John Jones, 35
Hannah Roberts, 9
Isaac Roberts, 4
all born in county
ref Piece 1402/Folio 7/Page5/Line1
Robert signed a will in 1846 which is on line at the NLW site year 1850
John Jones was his son
Hannah was his grandaughter. Isaac a grandson. In the will they are described as children of Robert's daughter Marry who was married to a Robert Roberts of Ty Mawr, which is listed lower down on the same census page. Other daughters were Elizabeth married to a John Owens and Jane w/o William Roberts.
HTH
Heather