Born in Ixopo Natal, S.A. He was one of nine children raised on various farms in the former East Griqualand region. His Grandfather was a McMillan from Scotland who may even have belonged to the same clan as former" British Prime Minister, Harold McMillan! His Grandparents apparently changed their name to Houston in 1850 at the time they arrived in S.A. Later in the century most of the family were adding in their real surname. Hence ""Houston"-McMillan"" is the family name in S.A. Alexander married Louisa Maria Maartens from Cedarville and together they had eight children, mostly in the Underberg area of Natal Province. One of the children died in infancy.