Thanks sillgen. It's reassuring to know where the information that confirms the gedcom can be found.
I agree that Thomas Comber senior was quite elderly to remarry, but the census record at Burnt Cottage in 1841 and at the Lindfield workhouse in 1851 are similar (along with MMN from GRO of his young daughters Ellen and Alice). By 1851 the children from his first marriage have gone off to make their own way in the world. I think I have found his children Sarah and William together in London on the 1871 census. William is a Chelsea pensioner after two decades in the army (including Yemen and Lucknow during the mutiny with the 78th regiment). He attested in Dublin in 1845. I have no idea why he was in Dublin then.
The gedcom is several years old and I believe the the person who originally compiled the information
(not the person who loaded all the names on a gedcom) is deceased. It was verging on a one-name study really. So in places it says "see notes" but I don't have access to the notes.
I'm particularly interested in Rebecca Overton. The gedcom says she was born in 1794 (based on her age when she died perhaps?) I'm wondering whether she could be the Rebecca Overton who was born in Broadwater in 1794, daughter of John Overton and Mary Longhurst. If she is then she is the sister of Sarah Overton who was born in 1797. I think Mary Overton nee Longhurst died in 1805 and John Overton died in 1811. I only found Sarah's baptism recently, and from that who her parents and siblings were. Sarah married Uriah Rolfe in London and is the mother of Harriet Rolfe who married Rebecca's son Thomas Comber in 1845 in London. Maybe they're first cousins.
The other thing I have spotted is that the middle name Penn comes up in both families. Thomas and Rebecca's son Edward Comber used the middle name Penn when he married. One of Sarah Rolfe's sons also had the middle name Penn (long before Thomas Comber and Harriet Rolfe married).
The gedcom has Sarah Overton and Uriah Rolfe's son Richard who was born in 1818 marrying a Jane Broad. Unfortunately at the parish level only a short transcript survives and not the full entry with fathers' names, occupations and witnesses, so I'd need to purchase the certificate for those details.
I've come across a marriage in 1839 of a Richard Rolfe to Mary Penn in London, and in later census records his age and place of birth don't rule him out as being their son, and I think it says his father is Uriah rather than Josiah. Mary Penn is the daughter of William Penn, and William was originally from Oxfordshire. I can see from place of birth of William Penn's children on census records that he must have lived in Lindfield when some of them were born and he has been an innkeeper. William died in London at Richard Rolfe's house in Edmund St. Richard married Hannah Maria Penn (who appears to be the younger sister of his first wife) a couple of years later. I had a post about the legality of that yesterday.
However Richard Rolfe's signature when he married Mary Penn isn't very similar to the signature of the witness at the marriage of Thomas Comber to Harriet Rolfe.
The short answer is that I have a tangled ball of string and maybe some of the loose ends tie up, or perhaps they don't. Perhaps it's all coincidence.