Du Toit's father was of Huguenot descent and his family had been in the Cape since 1687. His mother was the daughter of a Scottish immigrant.
Alexander Logie Du Toit was born on March 14, 1878, on his family’s estate near Cape Town. He was the eldest child of Alexander Du Toit and Anna Logie. His father’s family was one of the largest and most distinguished in South Africa.