Hi JeanieR
Am trying to find any small clue....
Are you already aware that the son James did appear to marry in 1844 to Harriet KITCHING, probably had a son born 1846 - and certainley a daughter in late 1848/early 1849 - then James died, and his probable son died both in late 1849?
James' widow (I believe) Harriet and daughter Mary are on the 1851 Census on the same Street as James' mother and 2 siblings. Will post up full details if you require them

The 1841 Census instructions meant ages of people over 15 were meant to be rounded down to the nearest multiple of 5 (and this LATTY family certainley has been rounded down). ie: Someone age 19, 18, 17, 16 should be rounded to 15. Someone age 59, 58, 57, 56, should be rounded down to 55
So, John & Jean showing as age 55 in 1841 (not 50) approximates born abt 1786 - BUT could both be as old as 59, born abt 1782. This is certainley true for Jean/Jane....
1851: 9 Woodman Street - South Leeds
HO107; Piece: 2319; Folio: 681; Page: 29;
Head: Jane LATTY 70, widow, Housekeeper, b Scotland (abt 1781)
Son: John LATTY 28, single, Coal Miner, b Scotland (abt 1823)
Dau: Jane LATTY 20, single, Rover Flax Mill, b Hull
Son: David LATTY 19 , Coal Miner, b Hull
1861: 9 Woodman Street - South Leeds
Head: Jane LATTY 79, widow, b Scotland
Son: John LATTY 39
Dau: Jane LATTY 29
In 1841 she would really be abt 58 or 59
In 1831/1832/1833 she would be abt 48 or 49 (when David was born) (David's age in later Census and death - all point to a year of birth abt 1832.
This makes Jane/Jean in her very late 40's, nearly 50 when she had both dau Jane and David?
How hold was John snr recorded as, when he died ?
Cheer
AMBLY