You are welcome Miles.
1851 Census HO107 Piece:2475 Folio:744 Page:16
William Roberts, b. 1802 Pembrokeshire, Ireland (?) Farmer
Mary , b. 1813 Begelly
Thomas, 1829
Samuel, 1833
Anne, 1838
Mary, 1840
Martha, 1841
George, 1843
David , 1845
LOT 1850
all born in Begelly
So, that is Lot's Father, Mother and siblings.
If you carry on through the census, you can find Lot with his wife and children right up to 1911
Search for a marriage for Lot and Martha etc....
Viv