About Boyer etc's father William's family - specifically Ann, his sister. She is not with the family in Castletown in 1841 when she would have been around 28. She appears back with her father and brothers in 1851 with John (7) and Elizabeth (2) noted immediately beneath her name as son and daughter, which can not relate to Andrew (Head) and Mary as they are about 80 years old! In 1861 she is with John and Elizabeth who are now described as nephew and niece. In 1871 John and Elizabeth do not appear with Anne, but another Ann is with her, also described as her niece and about the same age as Elizabeth. Ann is listed as a widow.
I have not been able to find any information about a marriage for Ann, nor for the births etc of these three children. It is possible Ann (younger) and Elizabeth are the same person (Elizabeth Ann Killip b. 1849?). It is possible the children were out of marriage (possibly by Thomas Teare who fathered a John Killip with an Ann Killip christened 31st December 1840)initially recorded as Ann's children then she became their aunt for social reasons.
Do you have any further info on these names or any thoughts to add to the conjecture?
On the line of William's father Andrew - 1841 census shows all the family born in Isle of Man. 1851 shows mother Mary and eldest brother Thomas born in Ireland - which seems to fit Mary McComb's name etc - probably born in Antrim. If the birth places for 1841 are dubious, then perhaps Andrew himself came from Ireland - there are a number of Killop families in northern ireland - if Andrew and Mary moved to the IOM with a young family to escape civil unrest (rebellion of 1798 in Antrim and Down would be a major memory)and/or famine, the Killop name would be likely to be transposed to Killip in the records as the Manx norm. There are very few Killip records in Malew prior to 1800 unlike other parts of the island and I can not link them to Andrew (yet!). Frances Coakley (www.isle-of-man.com/cgi-bin/interests/genealogy/bulletin/index) pointed out that Andrew is an unusual name in the Isle of Man for this time - this might suggest a migrant from Scotland (McKillop) or the Scots-Irish (Killop) - worth thinking about?
I've send this via the forum instead of direct e-mail in case anyone else has any contributions.