My wife's stepmother was a Van Antwerpen and was married and became a Van Zyl was then widowed and re-married and is now a Conradie.
I was researching the Conradie branch of the family when she came to visit and she has given me some info on the Van Antwerpens origin.
1st - Cornelius Jacob Van Antwerpen - Rotterdam Post
Married in holland but all children and wife died there.
Came to SA in 1763
Married in 1784 to Abigail Van Tonderen.
Frans Jacobus 26/5/1785
Susannah Elizabeth Franciena 21/5/1786
Jacoba Abigail 30/12/1787
Jacob baptised 31/5/1789
She has all original papers for above.
Please let me know if this is of interest to you and if you have any further information.