John Corkill is a tailor in 1881 and 1891, so looking for him prior to his marriage to Mary Jane Gelling nee Gelling:
Ancestry's transcription 1871
1871 Isle of Man Census
about Thomas Corkill
Name: Thomas Corkill
Age in 1871: 39
Estimated birth year: abt 1832
Relation: Head
Gender: Male
Where born: Bradden, Isle of Man, Isle of Man
Civil Parish: [Douglas]
Town: Douglas
County/Island: Isle of Man
Country: Isle of Man
Street address: View image
Condition as to marriage: View image
Occupation: View image
Disability: View image
Registration district: Isle Of Man
Sub-registration district: E
ED, institution, or vessel: 9a
Neighbors: View others on page
Household schedule number: 3
Household Members: Name Age
Thomas Corkill 39
John Corkill 16
Jane Corkill 9
Elizabeth Lace 30
Mary Dalton 61
Thomas, a widower, is a police constable.
John is a tailor's apprentice b Douglas.
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This is the only 1861 entry where I can match up a Thomas age circa 29 with a John circa 6.
Thomas 29 is a shoemaker b Braddan
Jane 35 is b Whitehaven, as is Thomas age 7.
CORKHILL John 6 Douglas 4418 57 15
Ancestry's transcription:1861 Isle of Man Census
about John Corkhill
Name: John Corkhill
Age: 6
Estimated birth year: abt 1855
Relation: Son
Father's name: Thomas Corkhill
Mother's name: Jane Corkhill
Gender: Male
Where born: Douglas, Isle of Man, Isle of Man
Civil Parish or Township: Conchan
County/Island: Isle of Man
Country: Isle of Man
Street address: View image
Condition as to marriage: View image
Education: View image
Employment status: View image
Occupation: View image
Registration district: Anglesey
Sub-registration district: Holyhead
ED, institution, or vessel: 7
Neighbors: View others on page
Household schedule number: 15
Household Members: Name Age
Thomas Corkhill 29
Jane Corkhill 35
Thomas Corkhill 7
John Corkhill 6
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This might be the burial of the Jane Corkhill nee ???? from Whitehaven.
CORKHILL, Jane 44 Braddan 27 Apr 1869
Donna, please would you see if there's an MI ?