Thanks for your reply Jeffrey. From what you posted I've put together this, from Manx Notebook, Familysearch and Ancestry censuses. I hope I've got it right.

Rushen 2 Sep 1792 CALLISTER John & MADDRELL Margaret with consent of her fa Thomas Maddrell [no parish ind] ipo John Nelson; Thomas Maddril {Manx Notebook cd]

Thomas Callister mar. Eleanor Kelley 1 Jul 1815 Malew [Familysearch digital folder number: 004497117]

Isabella Collister c.1823 Rushen, father Thos Collister [Familysearch dfn 004499930]

(1841) Glenchass, Rushen (dist 2) HO 107/1465/11 es.19 p.5
John Collister 75 Ind Y
Margaret 70 Y
Wm Collister 25 Ag Lab Y
Catherine Quark 15 FS Y
Thos Quark 5 Y

(1841) Glenchass, Rushen HO107/1465/11 e.s.18 p.2
Thos Collister 45 Ag L Y
Ellinor Collister 45 Yes e.s.18 p.3

(1851) Fistard, Rushen (dist.4) HO 107/2526 f.329 p.18 sch.70
Thomas Collister h m 58 Freeholder farmer 6 acres Rushen
Eleoner w m 61 “
Elizabeth Ronan serv 16 House servant “

(1841) Port St Mary, Rushen (dist.1) HO 107/1465/11 es.4 p.3
Nathaniel Pollard 45 Grocer – dealer E
Maria 40 Y
Matthew 4 Y
Shusannah 10 Y
William Sansbury 14 Y
John Sansbury 12 Y
Isaballa Collister 19 FS Y
Maria Pollard 1 Y

John Watterson m. Isabella Collister 9 Dec 1843 Rushen IGI ext

1851 Corvalley, Rushen HO 107/2526 f.325 p.11
Isabella Watterson wife 29 fisherman’s wife Rushen
Eleanor d 7
Margaret d 5
Ann d 3
John s 1

Can you tell me how you made the link between John Callister/Margaret Maddrell and Thomas Callister/Eleanor Kelly? I see you have a slightly different version of Thomas Callister's wife's name so I'm guessing you had a different source - perhaps the parish register?

Are you able to tell me any more about the Watterson brothers and their parents? I couldn't find a Thomas son of Thomas born 1813 on FamilySearch. Do you know their occupations - presumably ag lab/fishermen?

Best wishes

Sylvia