George Derham died on 9 February 1869 age 68 years at Stanpit near Christchurch.It seemed there was no will, because administration of the effects was granted to one of his sons in July 1876, a few months after George's wife Sarah died. According to 1851 and 1861 censuses he was born in Christchurch.
As far as I can find, the only Derhams born in Christchurch around the turn of the 19th century were either the children of James Derham and Betty Sibley or of James's brothers - John Derham (and his wife Mary Thomas) and Peter Derham (and his wife Sarah / Sally Hopkins).
There was another brother Joseph bapt 1765 in Morden before the family migrated to Christchurch, (he must have died pre- 1841), who may have married a Jane, because there is a Jane Derham of suitable age to be his widow with a Betsy Derham in 1841.
I think he is most likely to be James and Betty's child because they have John bapt 16 Apr 1797 and Walter bapt 01 Aug 1802, so a gap in the right place.
John and Mary have no obvious gap at the relevant time.
Peter and Sally didn't marry until 1803
Can anyone find George'e baptism please and confirm parents.
George is mentioned in passing here
http://www.rootschat.com/forum/index.php?topic=709513.msg5529608#msg5529608