This is really confusing. I can't see two William Duke / Juke marriages (or a baptism for Eliza/Lisa Duke), or a suitable burial for a Jane Duke, so I've listed out all the censuses which link them:

Jane says "Marown" in 1861, 1871 and 1881, but "Braddan" in 1851.
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1851
Ballaquinnea Beg cottage

Name Age
William Duke 35
Jane Duke 40
John Duke 8
James Duke 4
Rebecca Cannell 3

Wm b Arbory ag lab
Jane b Braddan
John+Jas b Santon
Rebecca niece b Braddan

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1861
Braddan 2/15
West Division, Castletown Rd

Name Age
William Duke 46
Jane Duke 48
John Duke 17
James Duke 14
Eliza Duke 9

Wm labourer b Arbory
Jane b Marown
John+jas b Santon
Eliza b Braddan

Wm Duke m Jane Cain 25 Jun 1842 Brad (ext)
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1871:
DUKE, William Head M 62 1809 Isle of Man
DUKE, Jane Wife F 64 1807 Isle of Man
DUKE, Lisa Daughter F 20 1851 Isle of Man
CAIN, John Boarder M 10 1861 Isle of Man
Address:Quay, South, Douglas County:Isle of Man

1881:
DUKE, Jane Head Widow F 60 1821 Kk Marown
CAIN, John Lodger Single M 19 1862 Labourer Kk Braddan
RG number:RG11 Piece:5603 Folio:105 Page:8
Address:7, South Quay, Braddan

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William Duke in 1851:

DUKE William 56 Arbory 2526 226 62
DUKE William 54 Arbory 2526 227 70
DUKE William 35 Marown 2523 277 3

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Jane Duke in 1851:

DUKE Jane 68 Rushen 2526 352 100
DUKE Jane 40 Marown 2523 277 3
DUKE Jane 25 Ramsey 2524 355 33
DUKE Jane 23 Arbory 2526 210 86
DUKE Jane 22 Arbory 2526 227 71

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William Duke in 1861:

DUKE William 66 Arbory 4409 26 69
DUKE William 64 Arbory 4409 26 67
DUKE William 46 Braddan 4412 27 71

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Jane Duke in 1861:

DUKE Jane 48 Braddan 4412 27 71

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William Duke in 1871:

DUKE William 77 Arbory 5778 19 75
DUKE William 62 Douglas 5776 149 131

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Jane Duke in 1871:

DUKE Jane 64 Douglas 5776 149 131

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The only ones which match up are the ones we've already got, or am I missing something ?

Rebecca Cannell, the niece in 1851, looks interesting.

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Rebecca Cannell bap 30 Jan 1848 St Barn Doug to Isaac Cannell + Eleanor (ext)

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Marriage isaac Cannell to Eleanor Cain 15 Jun 1844 Brad (pat sub)

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burial:

CANNELL, Eleanor 26 Braddan 23 Jan 1849

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Marriage Isaac Cannell to Eleanor Gelling 26 Oct 1851 Brad (ext)

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1861

Name Age
Isaac Cannell 40
Eleanor Cannell 31
Rebecca Cannell 14
Joseph Cannell 7
Agnes Cannell 5
Elizabeth Cannell 4
Christian Cannell 2
Robert Cannell 9 MO

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Does the Eleanor Cain b circa 1822, first wife of Isaac Cannell, help to tie anything together ?

Jean C