Looking for Information on Gunther

Looking for more information on Therese Gunther b.1868 left Germany 10 sep 1902 via hamburg on the Herzog to south africa with children Anna b.1894, Louise Theodosia b.1892 - d.1970, Ludwig b.1900.

Have no further information before or after except that Louisa married Charles William Niebuhr D.1947 Again no further information on Charles William Niebuhr. They had Freddy D.1943 & Willie.
Frederick Niebuhr married Dorothy Barbera Harris D.8/8/88 and had a son Aden Thomas (my father)B.7/11/41

Any information on either of these families would be appreciated.