GB is the youngest grandson of the English composer Sir Granville Bantock (1868 - 1946), who was knighted in 1930 for his services to music, and his wife Helena (1868 - 1961). He is also the youngest grandson of his maternal grandparents William & Alice More (1858 - 1934 & 1863 - 1927 respectively). William More was a reputed descendant of Sir Thomas More, one time Lord Chancellor to Henry VIII and author of Utopia.

Sir Granville & Lady Helena Bantock and William & Alice More