Lord Malcolm married firstly the Honourable Alice Frederica Irby, daughter of
George Irby, 4th Baron Boston, in 1861. After her death in October 1896 he married secondly Marie Jane Lilian, widow of H. Gardner Lister, in 1897. Both marriages were childless. He died at
Hyères, France, on 6 March 1902, aged 68, when the barony became extinct. He left his estate to his younger brother Colonel Edward Donald Malcolm (1837–1930), who also succeeded as Laird of Poltalloch. The latter's son was Conservative politician
Sir Ian Malcolm (1868–1944). Lady Malcolm of Poltalloch remained a widow until her death in August 1927. ==References==