Closing the series on islands in the Sound of Harris (Boreray and Pabbay went before), I am now focusing on Killegray and Ensay.
In the census returns from 1841 until 1901, the two islands cannot always be easily distinguished. Killegray only features as a separate enumeration district in 1841. In 1881, '91 and 1901, it is featured as a separate household schedule under enumeration district 1. It should be noted that in 1881 and 1901, this conclusion is only justified when comparing it to the 1891 census, where schedule 2 is clearly marked as Killegray House. The same people are still there in 1901, ten years older, but no longer separately marked. In 1881, it would seem that schedules 2 and 3 both refer to Killegray House; in 1901, this is schedule 2.
In 1841, there are 7 people on Killegray, 40-year old shepherd Kenneth Macrae with a 25-year old Mary Macrae. With them are 4 children under the age of 10. The seventh person is 62-year old Dorothy Ross.
As far as Ensay is concerned, in 1841, 16 people are registered as living there, 11 listed in the same household. The family is mentioned as "McCrac", but I would hazard a guess that being Macrae. Also present is a William McCaskia (Macaskill?), aa Mary Mckenzie and a Mary and Tilla "Maateld". The first names for those listed as "McCrac" were Alex (5), Alexr (20), Margt (25), Mary (15), Christian (20) and Alex (55). A separate family unit of McCrac consists of Christoph (30) and Isabella (25) with daughters Margt and Catherine (6 months). Effy Mccaskill (15) is in the same household.
 Kenneth Ferguson (19), brother-in-law and John Mcdonald (18), brother
 Christopher Macrae (40, boatbuilder, journeyman) and Bell Macrae (30); with children Peggy (12), Mary (10), John (8), Lexy (5) and Finla (3).
 William Macaskill (32, agricultural labourer) and Cathrine (30), with children Cathrine (9), Murdo (6) and Janet (2). These five are also mentioned under household 4, below.
 See those mentioned under , as well as:
Christy Mcrae (40, dairy maid), Janet Mckinnon (23, house servant), Duncan Mckinnon (20, farm labourer), John Mccleod (20, boatman), Donald Mcrae (19, boatman), John Mckinnon (17, herdboy), Mary Mccleod (16, house servant).
 Donald Mccar [Mcrae] (24, Ag Lab), Angus Mccear [Mcrae?] (30, ploughman), Angus Mccuien (57, Ag Lab), Andrew Mcrae (20, Ag Lab), Kristina Mcrae (60, Dairymaid), Margaret McOuish (22, domestic servant)
 Christopher Mcrae (56, boatbuilder, born in Kintail, Rossshire) and Isobel (40, born in Lochalsh, Rossshire), with children Mary (19, domestic servant), John (17, Ag Lab), Lexy (15), Finla (13), Donald (11), Agnus [Angus] (8) and grandson John Mcashall [Mcaskill] (3)
 Angus Martin (64, shepherd), and Cathrine (40), with children Donald (20, Ag Lab), Kenneth (15), Mary (11), Anne (9), Marion (7), Mary (5) and Johannah (2)
[2, Ensay House] Alexander Mcdougall (62, landoverseer, born at Fortingall, Perthshire), John Mcleod (50, Ag Lab, from Duirinish, Skye), Duncan Mclean (20, Ag Lab), Roderick Mcphee (18, Ag Lab), Morgan Ferguson (30, general servant / domestic) and Marion Ferguson (22, general servant / domestic)
[1, Ensay House] Duncan Mclean (29, farm grieve), Angus Mcleod (24, farm serv), Donald Mcleod (16, farm serv), Christy Mcphee (34, general serv, domestic), Catherine Shaw (44, dairymaid), Marion Mcaskill (25, housemaid),
[2, Kelligray House] Margaret Peterson (18, occupant, dairymaid)
 Donald Morrison (30, shepherd) and Mary (32, born in Lochbroom parish, Rossshire) as well as Donald's father Neil (64, shepherd). Donald and Mary's children were: Murdo (3, born in Lochbroom parish, Rossshire) and Neil (1).
[1, Ensay House] Donald Alexander Stewart (35, farmer) and his sister Mary (36), both born at Kilmuir (Skye). Marion Stewart is listed as a 23-year old cook; whether she is related to the previous two is not noted. Domestic staff include Effie Mcdougall (57, housekeeper) and Kate Mckay (19, from Kilmuir, Skye, domestic servant). Farm staff include Marion Mcdonald (20, from North Uist, dairymaid), John Mckenzie (40), Angus Mcleod (32), Donald Mcleod (24), Ewen Mclennan (19) and John Ferguson (46).
[2, Kelligray House] Mary Morrison (39, from Lochbroom, Rossshire, shepherd's wife) and her children Murdo (13), Neil (11), Rachael (9), Charles (7), George (5) and John (2). Christy Mcswen is a 17-year old domestic servant.
[1, Ensay House] William Stewart (48, born in Skye, Captain Mounted Infantry) and his sister Jane Macrae Stewart (50, born in Lochalsh, Rossshire). Jessie Chesholm Scott (42) is marked as a sister, but it is not clear whose sister she was. John Mckenzie (53, farm servant), Donald Mcleod (36, farm servant), Charles Morrison (18, farm servant), Alexandrina Rae (23, domestic house maid), Rachael Morrison (19, dairy maid).
[2, Shephard's House, Killegray] Donald Morrison (50, shepherd) and Mary (50), with their children George (16), John (13) and Simon (10). John Mckinnon is a 16-year old school teacher, boarding with the Morrisons.
I would like to once more applaud my fellow researcher Direcleit for accumulating a wealth of further information on these islands - this link refers to his entries regarding Ensay.