Born sometime before World War II, Sydney comes from a French/Belgian background (his father was in the Belgian infantry), and his family's background was devout Roman Catholic. Sydney's family includes his father John-Michael, his mother Gretta, and his identical twin brother, Jacob; a sister is also mentioned, but never elaborated upon. During World War II, Sydney's family is rounded-up by the Nazis; John-Michael and Gretta are sent to the gas chambers (despite the fact that the family was not Jewish), while Jacob and Sydney became the subject of experiments, since they are twins.