Source: Michael Doyle Their Name Liveth For Evermore: The Great War Roll of Honour for Leicestershire and Rutland.
He was the son of James Appleby a Domestic Gardener, born 1850 in Hurworth, County Durham and his wife Isabel, born 1853 in High Coniscliffe, County Durham. John Gill was born in 1886 in Hurworth County Durham, he had one sibling, a sister Harriet, born 1889 in Hurworth, County Durham, in April 1891 the family home was at Hurworth Hall, Hurworth, County Durham. In April 1911 John was an Assistant School Master and was residing as a boarder at 11, Severn Street, Leicester, his parents resided at The Green, Hurworth on Tees, County Durham, and he had an additional two siblings, Arthur, born 1892 and Edith born 1894, both siblings were born in Hurworth, County Durham. The Wyggeston Grammar School for Boys published a Roll of Honour on the 31st January 1920 in which an entry appeared showing him to have been a Master at the school from 1910 until 1914, it also recorded that he was killed in action while splendidly leading his men.