Hi
You have the 1841 and 1861 from the Mary lookups.
Here is the 1881
John Staffd Billsdon, head, age 73, lock keeper born Rutland Braunston
Sarah Billsdon, wife, age 72, born Leicestershire Tilton
Bridget Holmes, grand daughter, age 15, scholar born Lincolnshire North Kyme
North Kyme Fen Lock House
North Kyme, Lincolnshire
RG11 3221
folio 51 page 41
Nicky