The engagement was announced on 12 December between Walter John Francis Montagu-Douglas Scott, Earl of Dalkeith (b.2 August 1984)
[older son and heir of Richard Walter John Montagu-Douglas Scott, 10th Duke of Buccleuch & Queensbury (b.1954) & his wife Elizabeth Frances Marian, nee Lady Kerr, descendant of the Marquesses of Lothian (b.1954)] & Elizabeth Hanar Cobbe (b.1986)
[daughter of Hugh Michael Thomas Cobbe (b.1942) from the Irish gentry & his wife Katherine Elizabeth, nee Cichester].
Walter is second of four children and second one who marries; his sister Louise (b.1982) married Rupert James Trotter (b.1977) in 2011.
Charles (b.1987) and Annabel (b.1992) are still single.
Source: Peerage News: Earl of Dalkeith to marry Elizabeth Cobbe