The following will has a John Mylria & Ellinor Cain who is close to your date and might be yours:

15.
The Last Will & Testament of Joney Caine
als.Sayle of KK Michael who departed this
life about the first day of Feb:Anno Dui
1756. being of perfect mind & memory at
the making hereof ~ First She committed her
Soul to God and Body to Christian burial
Item She left & bequeathed to her four ~
Children vizt.Ellinor, Joney, John & Thos.
Twenty shillings each as Legacy, Item She
left her shaped linens betwixt her daurs.
& a piece of Stuff wch.was in the house for
Cloathes for them, Item She left & willed
that her husband should take Care to get
her sucking Child (namely Margt.) well ~
nursed & brought up and that , that would
be goods enough upon her part, Item
She left six pence each to the witnesses &
Lastly She nominated & appointed her sd.
husband Thos.Cain Sole Exer:of all the
rest of her Goods moveable & immoveable
whatsoever~
Testes | Willm.Cannell | Jurati

| Margt.Kelly |

At a Court of Correction held at KK Michl.Feb.18.1756
The Exect.is sworn in Court in form of Law & hath given pledges
offer payment of Debts & Legacies namely John Caine Sumnr.& Capt.
John Kaighin ~ he is to bring to the Registry an Inventory of the
Testris Shaped Linnen ~ Thos.Sale & Wm.Shimin the uncles by the
mothers side are sworn Supervisors of the orphans in form of
Law Probatum est
Solvit 12d. Matthw.Curghey

We Thos.Cain & John Mylechrist husband of Joney
Cain two of the Children of the within Testatrix Joney Cain
do hereby acknowledge to be fully paid & satisfied
our several & Respective Legacies of Twenty Shillings
each bequeathed us by the last Will & Testament of our Deceased Mother Joney
Cain & we do each of us hereby respectively acquit release
Exonerate & Discharge the Exrs.of th last Will & Testament of our said
Mother Joney Cain witness our Marks to our Names this
29th.Nov.1764~ [or 1784] Thos.Cain My X Mrk.
Before me Thos.Cubbon John Mylchriest My X Mrk.

I John Mylria husband of Ellinor Cain one of the Children of the
within Testatrix Joney Cain do hereby acknowledge to be fully paid
& satisfied the Legacy of twenty Shillings bequeathed My said wife Ellinor
Cain by the last Will & Testament of my said deceased Mother Joney Cain
& I do hereby acquit release exonerate & discharge the Exrs.of the Last Will
& Testamt.of my said Mother Joney Cain as Witness My Mark to my
Name this 24th.Janry.1784~ [or 1764] John Mylria his x mrk.
Before Me Thos.Cubbon

[transcribed from photocopy of microfilm 3 Nov 01 tcd]

[the following scrap was attached below & likely not related]
Michl. Augt.16.1757

Philip the half brother by the mother's side of Ellin,Daur.

of Ann Caine is sworn Supervisor of sd. Ellin in form

of Law
To be annexed to the will
of Ann Caine in Lib.xx.1756

[CAIN, Ann 1756-2 Mic A 40 0106221]

.1 Philip SAYLE
..2 Joney SAYLE Cain c.29 Sep 1717 Kirk Patrick bur.02 Feb 1756 Kirk Michael Cemetery
..2+ Thomas CAIN Sr
...3 Ellinor CAIN Mylrea c.24 Oct 1755 Kirk Michael
...3+ John MYLREA c.18 Jan 1753 Ballaugh d.06 Mar 1784 Ballaugh
...3 Joney CAIN Mylechreest
...3+ John MYLECHREEST
...3 Thomas 1 CAIN
...3 John CAIN
...3 Thomas CAIN Jr
...3 Margaret CAIN Corlett
...3+ John CORLETT III
....4 six children