He was one of the two stamvaders of the Van Wijk family who arrived at the Cape in the 17th Century. The other was Arij van Wijk. It seems likely that they were related to one another but how is not yet apparent.  

Willem van Wijk at the Cape  He first appears at the Cape as a Company servant, working in the Company's Garden in 1672. By 1678 he was a free burger, farming around Cape Town, working first in partnership with Gerrit Teunisz and then, from 1679 to 1685, with Hans Erntrout (?Hans Rutger Troost?).

His Farm  He and his family seem first to have lived in Cape Town, but from 1692 at the latest they were farming in Drakenstein. In the estate accounts drawn up after the death of his first wife, their farm was named as Sandwijk, and was situated in Drakenstein. They would seem to have concentrated on wine, with their number of vines rising from 2000 in 1692 to 6000 in 1702.  

His First Marriage - Trijntje Hillebrands  He married firstly Trijntje Hillebrands in 1685 at Cape Town. Occasionally in the Muster Rolls, she is given the surname Wijkens. I don't know if this refers to her own surname or is derived from that of her husband. She died between 1693 and 1695. Her estate accounts were drawn up on 10th March 1695 where she is noted to have left two surviving children. 

His Second Marriage - Trijntje Harmensz:  He married secondly Trijntje Harmensz: around 1694, probably in Drakenstein where they lived, since no record of the marriage survives. After Willem van Wijk's death, she married a second time to Jurgen Kervel (sometimes also Kerver) with whom she had several more children. In 1712 the Orphan Chamber called her to account for apparently not paying out their paternal inheritance to the two children of the first wife of Willem van Wijk.

Willem van Wijk's Children  

By his first wife, Trijntje Hillebrands, we know of three children:

  b1. Arij, baptised Cape Town 13 April 1686
   Around 1711 he  married Anthonetta Campher, 
   the widow of Gerrit van der Swaan,  
   and left 9 children when he died in 1731

  b2. Jannetie, baptised Cape Town 13 June 1688
   She would seem to have died before 1695.

  b3. Gerrit, date of birth or baptism not known.
   He married firstly Elisabeth Vivier in 1722
   and secondly Maria Provo (Prevost) around 1731.
   He died around 1737, leaving 8 children.

By his second wife, Trijntje Harmensz:, we know of another three children:

  b4. Maria
   She married Cornelis Pieters Stapper

  b5. Anna
   She lived first with Gerrit Willemse and then Isaac Nieuwoudt
   (or both at the same time?)

  b6. Willem
   He married firstly Johanna Catharina Campher in 1729
   and secondly Hendrina Monk around 1746.
   He died in 1756 leaving 9 children. 

Death of Willem van Wijk His death is noted in an Orphan Chamber entry dated 31st March 1702. In this same document, Trijntje Harmensz:, his widow, states that her husband had been beset with many illnesses before he died.  

SOURCES:

Cape Archives:
 Estate Accounts - Van Wijk, Willem Willemsz: 1756
 Estate Accounts - Van Wijk, Willem d'oude, 21 October 1772
 Inventory - Campher, Johanna Catharina, 2 May 1746
 Inventory - Hillebrants, Trijntjen, en nagelate man Willem van Wijk, 1695
 Inventory - Van Wijk, Arij, 1731
 Muster Rolls of Free Burgers (VC39, vol.1, p. 123 and p. 161, p. 179)
 Opgaaf (tax) rolls of Freemen at the Cape
 Provision for children of previous marriage - Provo, Maria, 1740
 Weesmeesteren: Extracten 1699 enz.
 Will - Helmes, Cornelia and Jacob Coetser, 1720
 Will - Van Wijk, Arij & Cornelia Helmes, 1713
 Will - Van Wijk, Gerrit & Maria Provo, 1731
 
Nederduitse Gereformeerde Kerk Argief
(in the form of microfilm copies)
 Cape Town Congregation - Registers of baptism and marriage
 Drakenstein Congregation - Membership Register
 Drakenstein Congregation - Registers of baptism and marriage
 Stellenbosch Congregation - Registers of baptism and marriage  

Research by:
 Richard Ball
who would have been unable to do this research without the help of André Kellerman, Helena Liebenberg, Graham Lloyd, Maureen de Villiers and Mansell Upham.  

For a more detailed account of the families and the evidence, see:

 Introduction to the early Van Wijks at the Cape
 Willem van Wijk and his family
 Notes on Trijntje Harmens:
 Arij van Wijk and his family
 
on Richard Ball's web site.