

Hello,
Can we get some sources for her supposed engagement to Granville George Leveson-Gower, 2nd Earl Granville I could not find anything concrete, just websites repeating that she got engaged to him in 1864 and then drowned afterwards while heading back to the Confederacy.
The one discussion I could found about this wrote:
"This is the man historians think was betrothed to Rose. His wife had died in 1860 and his
mother in 1862. This would lead one to assume he was probably looking for a new wife
during the time Rose was in Europe. Indeed about a year after Rose died he remarried.
Rose mentions him several times in the diary and appears to have enjoyed both his company
and the company of his sister Lady Georgiana Charlotte Fullerton. However, she gives no
indication in the diary that there is a romantic interest of any kind."
Does anyone know who these "historians" are and why they think she was engaged to Lord Leveson if there is no mention of this engagement in her diary? She certainly met him, and became friends with his sister, but what is the source for their engagement?
Thanks,
Tamas