Having spent some time looking at Caveen wills and studying Ancestry trees, I’m going to suggest that all the trees which include Thomas Caveen b 1782 (husband of Cath Harrison) have put him in the wrong family. I can’t see a single tree which has put him as “son of Richard Caveen”.

There were 2 children baptised as Thomas Caveen in 1782 in Arbory, TC 1) and TC 2).

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TC 1)

Name: Thos Caveen
Event Type: Christening
Event Date: 13 Jul 1782
Event Place: Arbory, Isle of Man
Event Place (Original): Arbory, Isle of Man
Gender: Male
Father's Name: Richard Caveen

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TC 2)

Name: Thomas Caveen • Edit
Event Type: Christening
Event Date: 11 Apr 1782 • Edit
Event Place: Arbory, Isle of Man • Edit
Gender: Male
Father's Name: John Caveen • Edit
Mother's Name: Elinor Quayle • Edit
Record Number: 2096

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This TC 2) (brother of your direct ancestor, Ralph) died in 1837 and was buried in Arbory 11 Aug 1837.

Copy of will transcribed by Shirley C Hogensen 2003:
Arbory
In the name of God Amen.
I Thomas Caveen of Balladoole in the parish of Arbory being weak in body but
of perfect mind and memory do make this my last will and testament in manner
following.
First I commit my soul to Almighty God and my body to a Christian
burial.
Secondly I leave and bequeath unto my beloved wife Jane Caveen the
whole of my right and title to the houses and gardens at the Green in the
parish of Malew also the houses and gardens at the Ballabeg in the parish of
Arbory.
Thirdly I leave and bequeath unto my two aunts namely Eleanor Caveen
and Margaret Caveen there life time of the house and garden the possesses.
Fourthly I leave and bequeath to my two brothers namely John and Ralph
Caveen the sum of five shillings to each of them as legacy.
Fifthly I leave and bequeath unto my two sisters namely Cathrine and
Ann the sum of five shillings to each of them as legacy.
Sixthly and last I nominate constitute and ordain my beloved wife Jane
Caveen sole and whole executrix of all the rest of my goods cash credits
chattels and effects of whatever kind or denomination she the said Jane
Caveen to pay unto any person or persons who shall claim or sue for any
thing contrary to this my last will and testament the sum of five
shillings as legacy ratifying and confirming this and none other to be my
last will and testament in testimony whereof I have hereunto subscribed my
name or mark this the 31st day of July 1837. Thomas Caveen. Witnesses:
Thomas Watterson
John Cannell my x

At a Chapter Court holden at Castletown 8th November 1837. The executrix is
sworn in court in form of law and hath given pledges for
the payment of debts and legacies namely the witnesses to the will.

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Marriage of TC 2):

Name:
Thomas Caveen • Edit
Event Type:Marriage
Event Date:21 Feb 1819 • Edit
Event Place:Arbory, Isle of Man • Edit
Gender:Male
Spouse's Name:Jane Cottier • Edit
Spouse's Gender:Female
Record Number:21

Image shows that both made an x-mark.
wit: Thomas Clague and Thos Caveen who both signed.

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TC 2)’s widow in 1841:

1841
Balladoole, Arbory

Ancestry’s transcription:
Name Age
Jane Caveen 40
Ann Kermodes 20
William Cottier 30

notes:
JC 40 independent
AK 20 FS
WC 30 MS

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1851
Strandhall, Arbory

Jane Caveen widow 61 farming 4 and a half acres b Rushen
(Ancestry has Jane Crawn)

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1861
Colby Road, Arbory

Jane Caveen 71 aunt widow servant b Arbory

(in household of Wm Qualtrough 35 and his wife Mgt 33 (nee Kinvig m 1851 Arbory) both b Arbory.
Wm Qualtrough was the son of Wm Qualtrough and Cath Cottier.)

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Burial of Jane Caveen nee Cottier:

Arbory 29 Jan 1871 age 81, Jane Caveen

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I’ll try to attach screenshots of the 1789 will of Ralph and Thomas’s mother, Eleanor Caveen nee Quayle, but you can find it on familysearch using the index number (106401) in this entry from the IOM wills index:

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CAVEEN Elinor QUAYLE 1789- Arb E w 0106401

It’s on page 678 of 756

The list of Eleanor’s children named in the will:

Thomas, John, Ralph, also Cath, Elinor and Margaret.

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One of the witnesses, Isabel Christian, became the second wife of John Caveen.

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Name: John Caveen • Edit
Event Type: Marriage
Event Date: 16 Feb 1790 • Edit
Event Place: Arbory, Isle of Man • Edit
Residence Place: Kirk-Arbory • Edit
Gender: Male
Marital Status: Married
Spouse's Name: Isabel Christian • Edit
Spouse's Residence Place: Kirk-Arbory • Edit
Spouse's Gender: Female

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Isabel and John had at least 2 children, Isabel bap 17 Oct 1790 and Ann bap 25 April 1796.

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John’s will:

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CAVEEN John 1815 Arb E 1 0106417

(images on pages 292 to 295 of 698)

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Isabella nee Christian was buried 1 July 1833 age 77 --- no will in the index.

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When Thomas Caveen b 1782 (TC 2) wrote his 1837 will, he listed his sisters as: Catherine and Ann. Ann was his half-sister.

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Now the other Thomas Caveen:

TC 1) Thos Caveen bap 13 July 1782, father Richard.

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Poss will of his father:
CAVEEN Richard 1821 Arb E 1 0106422

page 480 of 736

Dated 26 Aug 1816 --- has a son Thomas who is a “tayler of Castletown”

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and burial of his father
:
CAVEEN, Richard Arbory 23 Aug 1820

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So the Thomas Caveen (tailor) who married Cath Harrison was the son of a Richard Caveen.

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Jean C