[2] His sister, Katherine Isobel McEwen, married Roger Lumley, 11th Earl of Scarbrough, on 12 July 1922 at St Margaret's, Westminster, and had five children with him.

[5] McEwen served under Neville Chamberlain as Assistant Government Whip (1938–39), Under-Secretary of State for Scotland (1939 to 1940), and under Winston Churchill as a Lord of the Treasury (1942 to 1944).

The current holder of the title is his grandson, Sir John Roderick Hugh McEwen, 5th Baronet (born 1965).

The raised their family at Marchmont House on the east side of the small town of Greenlaw, Scotland.

[8] Together they had seven children, including:[9] He died in April 1962, aged 67, and was succeeded in the baronetcy by his eldest son James.