My father's brother was Petrus Albertus Venter (born c.a. 1900) and his son was P.A. too. These Venters were from the highveld area in what was known as Eastern Transvaal (now Mpamalanga), at Wonderfontein (near Machadodorp). I'm pretty sure that doesn't help you, except for the fact that Petrus Alberus seems to be very prominent family first & middle names.