Mr Clifford Thomas Jefferys was born in St Peter's Port, Guernsey in the Channel Islands on 8 April 1888.

He was the son of William John Jefferys (b. 1854), a general labourer, and Alice Ann Bennett (b. 1855), both Guernsey natives who had married around 1881. One of eight children, his siblings were: Lillian Elizabeth (b. 1882), Ada Alice (b. 1883), Frederick William (b. 1885), Ernest Wilfred (b. 1891), Hilda (b. 1897), William George Bennett (b. 1900) and Albert Edward (b. 1902).

Clifford first appears on the 1891 census living with his family at 3, The Green in St Peter's Port and again on the 1901 census at The Banks, 1 Elizabeth Terrace, St Sampson, his father now working as a stoker. His mother passed away sometime in early 1911 and by the time of the 1911 census Clifford is still at home, now Rosslyn in St Sampsons, Guernsey and he was described as a granite cutter.

His sister Lillian Renouf and brother Frederick had emigrated to the USA in 1907 and later settled in Elizabeth, Union, New Jersey. Lillian returned home in late 1911 with her husband Peter to pay a visit and upon their return to Elizabeth Clifford and his younger brother Ernest would be accompanying them. He boarded the Titanic at Southampton with his brother and a friend, Albert Denbuoy (joint ticket number 31029 which cost £31, 10s) and travelling with them, besides Peter and Lillian Renouf, were other Guernsey natives: William Douton, Lillian Bentham and Emily Rugg.

On the night of the sinking Clifford, his brother Ernest and brother-in-law Peter had been socialising in the smoking room when the collision occurred. They descended the decks to fetch Lillian Renouf who was in her cabin before ascending to the boat deck.

Clifford Jefferys died in the sinking. His body, if recovered, was never identified.

His sister Lillian survived and was returned to New York and was alerted to a news story published that bother her brothers were members of the notorious Doc Owen gang of card sharps who fleeced passengers on trans-Atlantic liners. Lillian and her brother Frederick were incensed over the story and declared they would sue those who were responsible for the story's publication.