Needham Bryan, II - The portrait does not depict Needham Bryan II.

The portrait shown does not depict Needham Bryan II. It is a 1768 painting of John Needham, 10th Viscount Kilmorey, by Thomas Gainsborough, acquired by the Tate Gallery in London in 1934. As late as 1885 it was still owned by the Needham family. Gainsborough's work is well-known, and John Needham was a well-documented individual, so we can be certain of the provenance of this portrait!

Please see here:
http://www.tate.org.uk/art/artworks/gainsborough-john-needham-10th-...

http://www.thomas-gainsborough.org/John-Needham.html

See also _Exhibition of the works of Thomas Gainsborough, with notes by F.G. Stephens_, written in 1885, page 22.

Gainsborough painted a portrait of John Needham's son Thomas Needham in 1768, the same year he painted John Needham.
http://www.nationaltrustcollections.org.uk/object/1535158