Great to hear from you. With regard to my book, there is not a great deal in it about the Jameson family from South Africa. My interest in the family came about because my husband's relative, Elizabeth Harrison, married Charles Jameson (Reyburn's brother) so I included an appendix at the end of the book with information about their father, Robert Jameson. Unfortunately, I do not have any information regarding his other children.
Good luck with your research.