Robert Albert Gray was born on 22 November 1899 at Neville in New South Wales to William Phillip and Julia Macquarie (née Sykes) Gray. He was the sixth of seven children. Robert, known as “Bob”, grew up in Neville and worked as a labourer and businessman of good repute.

Gray enlisted in the Second Australian Imperial Force on 18 June 1940, and was one of the first people from Neville to do so. After a period of training and illness, he embarked in late 1940. Gray was initially attached to the 1st Australian Corps Ammunition Park. However, he transferred to the 2/5th Australian General Hospital on 26 December 1940 and remained with the unit until the end of his service. With his unit, Gray treated sick and wounded servicemen in Palestine and Greece. After the evacuation of Greece, he was one of the 165 Hospital staff that remained in Greece to treat Allied sick and wounded. Gray was captured as a prisoner of war on 27 April 1941, and remained in Greece for another eight months where he continued working in the hospital . He was then transferred to Stammlager XXA at Thorn, Poland, and remained there for one year and ten months. In his time there, food was often scarce, and the prisoners had to depend on Red Cross parcels for sustenance. Gray was repatriated and returned to Australia, landing in Sydney on 27 February 1944. A record crowd welcomed him back home to Neville.

Gray was officially discharged on 22 September 1944, and resumed working as a labourer at Neville for several decades. It is unknown whether he married. By 1977, Gray had retired and moved to Orange.

Robert Albert Gray died on 29 May 1978 at the age of 78.