Re: Johann Hermann von Holten, born c. 1835, possibly in the Caribbean
Constance was Henriette's half-sister, as Johann re-married in 1862, in Slesvig, Denmark, to Minna Meyer, born 1840, also in Slesvig.
I suspect that they emigrated to the US due to the Second Schleswig War (1864).Constance was born in Charleston, South Carolina, US, 1865 June 27.
Constance subsequently married Ernst Halberstad, in New York, where she (mostly) lived, and presumably, died.
I say mostly because, once widowed, she also lived in Chile (1920s), and perhaps Bolivia.