Johanna was born in 1806 and her baptism took place on September 28th, 1806.
Birth Notes
http://archive.org/stream/OudeKaapscheFamilienPart1/OudeKaapscheFamilien-1_djvu.txt Full text of "Oude Kaapsche Familien Part 1" GESIACHT-REGISTER DER OUDE KAAP8CHE FAMILIEN Gecompileerd door Ghristoffel Coetzee de Villiers