Update: Murdo’s parents were, according to his Marriage Certificate, Angus Mcdonald & Christy Morrison. The 1901 census shows the following:
Christina Mcdonald, 59, Woolspinner, No 46 North Harris*, b. Harris
Marion Mcdonald, 21, Daughter, b. Falkland Islands
(*North Harris with a No. is probably 46 Tarbert, the 1901 Census not specifying Tarbert addresses)
There is no record of either of them in the 1891 census.
Although I have been unable to discover their voyage from the Falkland Islands to the Isle of Harris, I find it tantalisingly plausible that this mother and daughter are Murdo’s mother and sister. If so, then his mother was born in Harris and it is interesting that there is one marriage recorded between an Angus Macdonald and a Christina Morrison on the island. It took place in 1871 and so we can imagine the couple marrying prior to their departure for a new life many thousands of miles away, at least two children resulting from their union and then these two and their mother returning to the isle of their parents birth.
I will, in due course, examine the Marriage Certificate which, together with a search for and examination of the Death Certificates of these three, should settle the matter.
Update: I was interested in learning about population figures for the Falkland Islands and eventually found these tables showing 811 people in 1871, 1510 in 1881, 1789 in 1891 & 2043 by 1901. There is an informative timeline and much other useful information to be seen on the site.