Macklin's father was the automotive entrepreneur Noel Macklin, founder of both the Invicta and Railton car companies, as well as Fairmile Marine, a manufacturer of motor gun and torpedo boats during World War II.
O pai de Macklin era o empresario automotriz Noel Macklin, fundador tanto das compañías de automóbiles Invicta e Railton, ademais de Fairmile Marine, un fabricante de motores e torpedos durante a Segunda Guerra Mundial.