Hi Lyn
Per the 1881 Census, below: If this is the right family, it looks as if Alexander did have a brother Donald , also one called Kenneth, and a sister Margaret. It also appears his father Roderick McKENZIE was dead by the time of the Census. The age of children Margaret, Donald & Kenneth in Census matches IGI births to Roderick McKENZIE & Christy McPHERSON. IGI also has other children: Annabella(1860) and Isabella (1862) but did not find them on Census - possibly either died young or married by 1881.
1881: Inveralligin Road. Applecross, Ross & CromartyVolume 058/2 ED: 2 Pg 3
Head: Christian MC KENZIE, 46, wid, b: Applecross, Ross and Cromarty
Dau: Margt MC KENZIE, 16 , unm, Servt, b: Applecross, Ross and Cromarty
Son: Alexr MC KENZIE, 12 , Scholar, b: Applecross, Ross and Cromarty
Son: Donald MC KENZIE, 10, Scholar, b: Applecross, Ross and Cromarty
Son: Kenneth MC KENZIE, 7, Scholar, b: Applecross, Ross and Cromarty
Cheers
Anne NZ
