William Willis was born in Southampton, Hampshire, England in 1853. His birth was registered in the first quarter of 1853 and he was baptised on 19 June that same year. He was the son of John Knight Willis (b. 1815 in Poole, Dorset) and Luanna Light (b. 1820 in Eling, Hampshire) who had married in Southampton in 1845. He had two known siblings: John Light (b. 1846) and Laura (b. 1850).
William first appears on the 1871 census as an 18-year-old plasterer and still living with his parents at 20 St Mary's Road, Southampton. His father was described as a bricklayer at this time and would later pass away in 1873.
William was married in Southampton in late 1880 to Emma Dukes (b. circa 1853 in Southampton) . Together they would have five children, with four living past infancy: Blanche Edith (b. 1881), Alfred Edward (b. 1887), Mabel Ada (b. 1888) and William Henry (b. 1891).
William, his wife and first child Blanche appear together on the 1881 census whilst living at 70 James Street, Southampton and he was now described as a dock labourer. The census reports in following years suggest dysfunction within the family, with William always being absent (perhaps at sea) but with his wife claiming to be a widow in the 1891, 1901 and 1911 censuses; the 1911 census reports that she was a widow following thirty years of marriage. On the 1891 and 1901 censuses William's "widow" is residing with her children at 7 Melbourne Street, Southampton. On the 1911 census his wife and son William Henry are living together at 106 Millbank Street, Northam, Southampton, his son being described as a messenger for the gas company.
When William signed-on to the Titanic, on 6 April 1912, he gave his address as 59 Derby Road, (Southampton) which was the home of his brother John Light Willis, a plasterer, and his family. His last ship had been the New York. As a third class steward he received monthly wages of £3 15s.
Willis died in the sinking. His body, if recovered, was never identified.
William's widow Emma's whereabouts following the death of her husband are unclear, but she may have remarried.
His daughter Blanche Edith was married in 1907 to Ernest Frederick Barber, also a mariner, and they had one son in 1911 named Henry. She died in 1966 in Southampton. His son Alfred Edward had been married in 1908 to May Stote and raised a family, later working in the gas works. He died in 1962 in Southampton. His daughter Mabel was married in 1919 to George Watson and she died in Winchester in 1970. His son William Henry later married before his death in 1962.