When a Prime Minister orders troops off to war, it is rare for him to personally know those who die in the conflict.
But now the poignant story of how a servant at 10 Downing Street died in the First World War has come to light - and the grief of his former master.
Robert King had been working as a batman to Prime Minister Herbert Asquith before fighting for King and Country.
Mr King had signed up to fight in a rifle brigade - but died after being shot in the thigh during fighting in Palestine 11 months before the end of the war.
Now 91 years later, letters from the PM's wife and photographs of Asquith's former trusted manservant have been discovered.
An emotional letter from the Prime Minister's wife, Margot Asquith, is included in the collection that is to be sold at auction tomorrow.
Mrs Asquith, a direct ancestor of the actress Helena Bonham-Carter, wrote to Mrs King:
'Your son Robert was a great gentleman, a born friend and we were all devoted to him.'
The letter continued: 'Your son has died the highest death you can die.
'He has died for his country and you will be proud of that poor Mrs King... How deeply I feel for you, I cannot even begin to express.
'Mr Asquith joins me in sympathy for you over our dead Robert's death.'
At war: Private King, top left, with members of his platoon in Palestine
Black-and-white photographs show him immaculately dressed at a Royal banquet in Downing Street and then in combat fatigues, smoking a pipe with his Army unit.
Rifleman King was fighting for control of Palestine then in the grip of the Ottoman Empire - which later became Turkey.
His death, in 1917, while he was thought to be in his mid 20s, is detailed in several letters, including from Reverend Webster, the chaplain attached to the unit.
Rev Webster wrote to Mrs King: 'He was brought to us suffering from a gunshot wound in the thigh on 13 December.
'...everything was done for Mr King, but he passed away next day on 14 December.'