Joyce Oates has transcribed the two wills of Isabel Callow's grandparents:

Archdeacon Will 1689A #148 Maughold will of Joney Kerruish alias Corlett, of Ramsey & Leaghyrney, died about December 1689:
Summary: husband Ewan Kerruish, son in law? John Callow, grandson William Callow, granddau Margaret Callow, granddau Isabel Callow, grandson John Callow, granddau? Joney Callow, dau Joney, dau Isabel, sister Margaret Corlett, brothers Robert Corlett & xxxx Corlett

The last will & Testamt: of Jony Corlett -------[dark]
being sick & weak of body & of good & perfect -------[dark]
her soul to God & body to Xtian b-------[dark]
Item She left and bequeathed to her -------[dark]
her half of the Lands of the Leaghern-------[dark]
husband Ewan Kerruish he her sd husband haveing -------[dark]
benefitt therof dureing his naturall life, and ther upon -------[dark]
gave his full consent & Assent that the sd: John Callow s-------[dark]
whole as well as his half as his wife’s after his decease.
Itm: She left to her grandchild Willm Callow her part of -------[dark]
land purchased from Willm: Kneal after her sd husbands dec-------[dark]
he haveing also consented to give the whole after his death
provided that if ye sd Willm: dye wthout Issue the same is to fall to Jony Callow
Itm: She left to her grandchild Margt: Callow her pt of the -------[dark]
in ye west end of ye town after her husbands decease, & the w-------[dark]
after his death wth his consent
Itm: to her grandchild Issabell Callow her pt of the houses & g-------[dark]
on ye mooregh after her husbands decease, he giveing his c-------[dark]
for the whole at yt time as above mentioned Itm: She left to her daughter Jony 12s and a blankett legasy
Itm: She left to her daughter Issabell 2s - 6d
Itm: She left to her grandchild John Callow the lands of Bal-------[dark]
and houses after her husbands decease to wch he gave his con-------[dark]
Itm: She left to her sister Margt: 2s legasy. Itm: to her brothers ---------[dark]
& Robt: 2s a peice. and lastly constituted & ordained her -------[dark]
ing husband Ewan Keruish sole Execr: of all the -------[dark]
of her goods moveable & imoveable wt:soever
The Execr: sworn in form ot -------[dark]
Testes Jon:Christian }
Edmond Corlett} jurati
Probatum et solvit -------[dark]
…………………….

Isabel Callow married William Kerruish 20 Jan 1690/91 Maughold. (William Kerrish/Kerruish“of Carradell/ Cardel/ Cardle”.)

Her grandfather Ewan Kerruish (widower of Joney, above):

KERROUSH, Ewan 1694-2 Mau A w 0106206
This is affirmed by the witnesses to be the last will & testament of Ewan Kerroush
who was of perfect memory comitted his soule to God & his Body to Christian burial,
he bequeathed to Ewan Kerroush of B:negory ten shillings
Itt, to his brother Willm of B:negory ten shillings wth his apparel betwixt them.
Itt, to Parsson Christians wife 2 shillings 6d legasy.
Itt, to Capt Xtin’s wife of K Bride 2 shillings 6d legasy.
Itt, to Edwd Callow ten shilling ---- by wife & ten shillings.
Itt, to Jon: Casmt: & his wife ten shillings.
Itt, to Edwd Callows two daughters ten yeards of linen cloth.
Itt, to Jon: Casmt: daughter a choise blaneket.
Itt, to Ewan Kerrish son of Willm of B:e cregan a heifer.
Itt, to the sd Willm: of B: e cregan his wife Isable their children the houses
& garden one the mooraugh.
Itt, to the said Willm: all his sheep.Itt, to John Callow son of Edwd his part of the houses & lands in the Leyharny.
Ittm, to his bro: Willm: Callow his share of Curraugh Roose, moreover the sd
Jon: Callow ask’d the Testator what he should doe wth him for wt he was behinde wth him,
who reply’d that he should pay it this yeere [‘this yeere’ is crossed out]
& then be cleere wth them, meaning the ------- [veedq--- OR reedq--- OR reaq--- OR ?].
Itt, to the above Jon: Casmt: his share of the garden at Edwd Callows house of 2d rent;
and constituted & appointed the above sd Willm: Kerrish of B: e creggan &
Robertt Kerrish Senior of Cardayle sole Executors of all the rest of his goods wtsoever.

Wittnesses present: Jon: Casment, Ewan Crowe, jurati.

The Execr sworn in Court according to Law. Probatum est et Solvit 6d.

Ewan Crow one of the witnesses declareth that abt five weekes after the making
of the above will, the sd Testator sent for him and declared before him that he
left fourty shillings of the mony under the Custody of Robt Kerush to his nephew
William Kerush of Ballnagorry, and the rest to be bestowed upon his ffuneral.
[Joyce M Oates]

In 1712 Isabel herself bequeathed “to her son Ewan, the house and garden in Ramsey
(upon further consideration she asked her husbands consent to the said bequ--- and he replied perchance wee shall not differ)”. Ewan was the 2nd son and unmentioned in his brother and father’s wills (perhaps because he already had the house?).

“Ramsey” (by C.R.) “A John Kerruish who bought a plot near Ramsey farmhouse in 1635 belonged to the Ballacreggan family, as did a William who bought a parcel on the Mooragh in 1673. John’s ground passed to the Callows who inherited Ballacreggan (see Callow), while William’s (part of the Swimming Pool) came to his grandson Thomas Kerruish, a cooper (1706-86).”

I still haven't discovered how the "swimming pool" could have had houses and garden.

Sue