Source: Michael Doyle Their Name Liveth For Evermore: The Great War Roll of Honour for Leicestershire and Rutland.
PD He was the son of Mark Collis a Police Sergeant, born 1855 in Knighton, Leicester and his wife Harriet Eliza, born 1852 in Wigston Magna, Leics. Mark Sidney was born in 1895 in Mountsorrel, Leics., his siblings were, Fanny J., born 1881 in Wymeswold, Leics., George E., born 1885, Emily F., born 1886, Harriett E., born 1887 and Lucy A., born 1890, the latter four siblings were all born in Castle Donington, Leics., Albert Edward, born 1893 in Mountsorrel, Leics., in March 1901 the family home was at Quorn Road, Mountsorrel, Leics. In April 1911 Mark was employed as a shoe trade laster and was residing in the family home at Nook Lane, Barrow upon Soar, Leics., together with his widowed father, now a police pensioner and his brother Albert, also residing with the family was his married sister Bertha Elizabeth Simpson, born 1878 in Loughborough, Leics., and her husband, James Simpson a shoe trade clicker, born 1878 in Dublin, Ireland and their children, Mark Edward, born 1903 and Margaret Vera, born 1906, both the children were born in Mountsorrel, Leics.