Couldn't see any in Shillington in 1851. **see later
Found the following in Pirton, Herts 1851
HO107/1710 folio 299B
Burgend, Pirton
George Catterell head marr 33 ag lab born Pirton
Ann Catterell wife 34 b Pirton
John Pearce father in law widower 82 b London
Burgend
James Catterell head marr 24 ag lab b Pirton
Abigail Catterell wife 23 b Pirton
Elizabeth Catterell dau 4 scholar b Pirton
Mary Catterell dau 2m b Pirton
Wet Lane Pirton
William Catterel head marr 62 ag lab b Pirton
Abigail Catterel wife 59 b Pirton
Thomas Catterel son unmarr 20 ag lab b Pirton
Sarah Catterel grand dau 11 scholar b Pirton
There was a burial of James Catrell, infant at Shillington on 6 Mar 1849
There are also a number of member submissions on the IGI for this family (which I normally take with a healthy pinch of salt), indicating that William was buried on 5 Jan 1851, and there is a burial of William Catterell aged 29 on this date at Pirton on the NBI. Whilst this would explain why I can't find William in 1851 I don't understand where Mary and George have gone!
Judging by the member submissions on the IGI the William and Abigail in Pirton in 1851 were William's parents.
OK, panic over. Had another look at Shillington:
Mary Catherall head widow 29 straw plaiter b Houghton, Beds
George Catherall son 5 b Shillington
Mary A Catherall dau 1 b Hexton
Mary Buckingham lodger unm 21 straw plaiter b Shillington
Hope this helps
regards
David
David