He was the son of the founder father Antonie Petrus Phillips Rosenkrantz born n Trier , Germany. Married to Helena Dorothea Johanna Goussard. Born 14 Nov1808 and baptised in the Lutheren Church, Cape Town. She was the daughter of Anton Goussard.
Johan Anton was likely named after Helena's father. I have found no proof that Johan was born in Worcester, however it is known
that he was baptised on his mothers wedding day. to witt 10 April 1830. I suspect that he was not the son of the Rosenkrantz founder father.