I have info on Patrick s/o John Cowley/Isabel Cannell.
He was ch 19 Mar 1697 Michael
md Joney Caine 29 Nov 1740 Jurby
Children with Joney Caine
John Cowley abt 1741-30 May 1796 Michael will 106405
Mary 1 Mar 1743 KM-4 Jan 1814 KG m wm Killip 6 Nov 1768 Will #57 106239
Alice 8 Jul 1744 Michael, died as infant
David 14 Jan 1747-21 Jul 1830 m Catherine Quayle 16 Nov 1777 KM will 106430
married Margaret Cubbon 1749
Children with Margaret Cubbon:
Catherine abt 1750 KM-28 Aug 1805 m Thomas Quayle 3 Nov 1789 KM
Ellinor 21 Jun 1752 KM m John Clarke 29 Sep 1782
Margery 12 Nov 1754 m Wm Joughin 11 Mar 1800 no issue
Margaret 24 Apr 1757 KM

EPISCOPAL WILL Kirk Michael 1765 FHL Film #0106388:
The last will and testament of Patrick Cowley of East Knockbane in the
parish of KK Michael being weak in body but of perfect mind and memory
at the making thereof the day of year above mentioned.
FIRST - He commended his soul to God and body to christian burial to his
son David he bequeathed the sum of two pounds ten shillings as also a
sheep over and above what was due to him by the death of his mother.
To his daughter Mary he bequeathed the sum of one pound ten shillings as
also the white chest, besides what was due to her by the death of her
mother.
To her daughters Cath: Ellinor, Margery and Margaret children by a latter
wife he bequeathed the sum of forty shillings each with two sheep
between them.
He left and devised his part of the feather bed, bolster, and cloaths
belonging to said bed unto his wife as also a white chest.
LASTLY - He left and bequeathed all the rest and remainder of his goods
of what denomination soever unto his eldest son and heir namely John
Cowley, whom he also appointed sole executors of this his last will and
likewise supervisor of his children under age, requesting at the same
time that the Reverend James Wilkes Vicar of the parish would also be
one of the supervisors of his said children.
Witnesses: Ja: Wilkes

Henry Kewley.
At a Chapter Court holden at the KK Michael Oct 25 1765.
The executors is sworn in court in form of law, as also supervisor of the
children under age the deads part of whom with their goods he
undertakes and has given pledges for payment of debts and legacies
namely John Sayle and Henry Kewley junior both of KK Michael. The
widow is also sworn to render a just record of the goods of the
deceased.
Matths Curghey
At Ballaugh Jul 2, 1773: Wm Killip husband of Mary Cowley
acknowledges to have received from John Cowley executor of the will
and testament of Patrick Cowley all and every the legacies bequeathed
unto his said wife by the said testor and hereby acquits and discharges
the said John Cowley his executors and administrators of the same.
William Killip
At KK Malew Oct 28th 1780 Ellinor Cowley acknowledges to have
received from John executor of the last will and testament of Patrick
Cowley all and every the legacies bequeathed unto her by the testor her
father Patrick Cowley and hereby acquits and discharges the said John
Cowley his executors and administrators of the same. Witness her hand
X Mark before me Wm Clucas - Ellr Cowley her X Mark

I have more info on this line if this is the right one, also info on Joney Caine's line.

Sorry I don't know about Gilbert Cowley et al