John William Pett was born in 1876, the son of William, an engine fitter, and Mary Pett (née Heard). William was born in 1851 in Cornwall and Mary Jane Heard was born in 1853 in Wales. They were married in 1875 at Pontyprid.
John William married Sarah Evelyn (Evelyn) Gregory on 8 July 1903 at St Mary's Church, Ilkeston. They had two children, John (Jack) Evelyn born 3 July 1904 and Richard (Dick) Charles born 7 May 1916; both children were born in Bulwell, Nottingham.
In 1911 John William, a commercial traveller in hardware on his own account (working from home), was a boarder at 89 Alfreton Road, New Radford, Nottingham, in the home of Agnes Weldon, a fancy drapery dealer. Evelyn and their son Richard were living at 191 Wollaton Street, Nottingham, with her widowed mother, Emma Jane Gregory, while her son John was living with his paternal grandparents, William and Mary Jane Pett, in Treharris, Glamorgan.
John named his wife and sons as his next of kin when he enlisted in 1914. The family's original address was deleted (illegible) and altered to 2 Hampden Cottages, Russell Street, Portland Road, Nottingham. This was given as Evelyn's address on the later CWGC record.
In 1939 when the England & Wales Register was compiled, Evelyn and her son John, a builders' labourer, were living on Gregory Boulevard, Nottingham, with Evelyn's unmarried sisters, Helen, a milliner, and Minnie a milliner's assistant. Evelyn's occupation was given as housekeeper. Richard (no occupation) was a patient at a 'Public Assistance Institution', 700 Hucknall Road, Nottingham. Evelyn died in 1966.