Miller's first wife was Belinda Stewart-Wilson, who guest-starred with him in Series 3 of Primeval. The pair, who have a son Jackson, known as Sonny (born in 2006), divorced in 2011. Miller has another son, Harrison, born in late 2011 and a daughter born in June 2015, with his second wife, production executive Jessica Parker, daughter of British musician Alan Parker, whom he married in September 2013.