
1942 Johannesburg driver's licence — names and photograph match the FamilySearch profile and date him to Johannesburg by 1942 (the family had moved from the Cape by then).
Family document, supplied by Attie Retief.
Attie’s maternal grandfather. Born 22 February 1920. The 1942 Johannesburg driver’s licence and 1955 identity card — both supplied by the family — anchor him independently of the tree records: they match the FamilySearch profile (GLMV-MXY) exactly and place him in Johannesburg by 1942. He had married Anna Susanna Margrietha Fuller three years later at Jacobsdal in the Free State.
His name — Johan Wilhelm Albertus — is not chosen at random. It carries down the full Christian-name block of his maternal grandfather, Johan Wilhelm Albertus van Niekerk (1864–1938), across a surname change. See the naming-echo thread.

1942 Johannesburg driver's licence — names and photograph match the FamilySearch profile and date him to Johannesburg by 1942 (the family had moved from the Cape by then).
Family document, supplied by Attie Retief.

1955 South African identity card.
Family document, supplied by Attie Retief.
Civil marriage record — Johan Wilhelm Albertus van Zyl × Anna Susanna Margrietha Fuller, 6 January 1945, Jacobsdal, OFS.
South Africa Civil Marriage Records, 1801–1974.
Two family artefacts — a 1942 Johannesburg driver's licence and a 1955 SA identity card — both match the FamilySearch profile of Attie's grandfather exactly. As solid as 20th-century genealogy gets without a parish register.
Attie's maternal grandfather, Johan Wilhelm Albertus van Zyl (b. 1920), carries the full three-name Christian block of his own maternal grandfather Johan Wilhelm Albertus van Niekerk (1864–1938). Grandfather's father to grandson, preserved intact.