Not sure whether these are connected but posting in case.
I've not tried to analyse any of them.
I'm only posting briefest of detail because I'm very lazy!
All have Kilmarnock / Ayrshire connection. Some Irish births.
Can look again if any mean anything to you.
There are other spelling variations too, eg, Kellahon, Kellochan
This is not an exhaustive list.
1891 may be of particular interest.
Dave
I'll go back in and amend this post - I've mixed up years. sorted
1901
Address: John Finnie St Drell Hall
ED: 26
Household schedule number: 95
Line: 5
Patrick Keleghan 42
Ellen Keleghan 38
Winfred Keleghan 18
Mary Ellen Keleghan 13
Catherine Lousia Keleghan 11
Edward Keleghan 9
Earnest Walter Keleghan 6
1891 1901
Address: 12 Boyd St
ED: 2
Household schedule number: 242
Line: 21
Robt Neil 32
Lilly Neil 53
Joseph Neil 26
Helen Neil 22
Jas Neil 13
Lilly Kellahin 76 Aunt
1891
Address: 1 Cotton Row. Irvine
ED: 4
Household schedule number: 123
Line: 7
John Kellachin 86
Maria Kellachin 63
ED: Cunningham Combination Poorhouse
Household schedule number: 1
Line: 8
Wm Kellahin 67
Margt Kellahin 67
1881
Address: 7 Kirk Vennel, Irvine
ED: 3
Household schedule number: 49
Line: 23
John Kellachan 75
Maria Kellachan 49
Address: 29 Calder St, Blantyre
ED: 5
Household schedule number: 173
Line: 10
Joseph Kellochan 34
Mary Kellochan 30
Daniel Kellochan 5
Patrick Kellochan 3
Roseann Kellochan 1
Agnes Kellochan 7 Mo
Address: 47 Strand Street, Kilmarnock
ED: 24
Household schedule number: 141
Line: 18
Roll: cssct1881_190
William Kellachan 57
Margaret Kellachan 57
Address: 1 Jacksons Close, Edinburgh
Robert Ferguson 32
Mary Ferguson 37
William Kellahn 77
David Kellahn 7
Robert Ferguson 6 m
1871
Address: 36 Low Glencairn, Kilmarnock
ED: 24
Household schedule number: 258
David Kellighan 36
Agnes Kellighan 34
John Kellighan 15
Joseph Kellighan 14
Elizabeth Kellighan 12
James Kellighan 5
Catherine Kellighan 4
Agnes Kellighan 1
1861
Address: 9 Braeside, Kilmarnock
ED: 16
Household schedule number: 94
Line: 14
John Kellahin 57
Margaret Kellahin 41
(this is not the one Carole quoted - same address though)
20 College Wynd, Kilmarnock
ED: 12
Household schedule number: 122
Line: 1
Mary Kellahin 50
Thomas Kellahin 35
Mille Kellahin 30
1851
(mentioned by Carole)
West Back Road, Kilmarnock
ED: 3
Page: 38 .
Household schedule number: 169
Line: 4
Robert Kellahin 23 (I love this occupation - Stakiner Purter ( Borkseller)
Mary Kellahin 18
Mary Dickie Killahin 8 Mo
Mary Alexander 58
1841
Fore Street, Kilmarnock
Parish Number: 597
John Kellachan 35
Robert Kellachan 14