Good Morning Faye. It has been almost 2 years since your posting and our previous dialogue. Since that time I have managed to purchase the series of genealogical records encompassed by "THE EDDY FAMILY IN AMERICA"and have the following information about our EDDY ANCESTRAL LINK - not necessarily new information to you but thought I would provide what I have.
1. Louisa Eddy -Eddy Family Association Genealogy No. 4266 b. 21 January 1844 m. Joseph Roberts in 1868 d. 26 December 1895
2. John Roberts b. 1802- Cornwall, England m. Francis Vivian daughter of Stephen Vivian (1785-1839) e. emigrated from England with wife in 1846 d. 4 March 1888, Townsend
3. Francis Vivian (Fannie) b. 22 November 1813- Little Petherick, Cornwall, England d. 27 October 1905
4. Stephen Vivian b. 14 February 1785 m. 30 January 1808 to Mary Ball (1790- 1847) d. April 1839
With respect to Lord Richard Hussey Vivian, there is quite a bit of information available on him, including a portrait which is in the National Gallery in London.(this may be the portrait copy on the wall you mentioned) However, I haven't been able make a connection between Lord Vivian and either of the Peter Vivians that may have been Stephen's father.
In this regard, if you have any further information about the above VIVIANs, I would be delighted to hear from you with any detail you can provide as, you indicated, the family tree gets very complicated. By contrast, the EDDY's are very well documented.
By way of reciprocation, I have the entire EDDY Ancestry back through Louisa's father Constant, if you need any of that information from the 6 books I have purchased from the EDDY FAMILY ASSOCIATION - although you may already have all of that, or at least access to it.