When the 1901 Census was taken, Gilbert was a 15 year old errand boy living in the Collyhurst area of Manchester. The family home was at 11 Franklin Street. His father, Thomas, was then 40 and earned his living making revolving shutters. His mother was 38 year old Alice. Gilbert had an older sister, May, and four younger siblings (Thomas, Elsie, Robert and Laurence).
In later life, he married Catherine. Family history websites indicate this may have been Catherine Chandler who married a Gilbert Clarkson in the December quarter of 1911 in the West Derby area of what is now Merseyside.
By 1916, the couple had moved to Bramhall and were living at 66 Bramhall Lane. They now had two sons, Eric and Ronnie. Gilbert worked as the manager of the Dom Picture Palace, also on Bramhall Lane until he enlisted into the army in June 1916.
There are few details in official records of the days leading up to Gilbert's death. After a period in reserve, the Battalion went back into the trenches near the French village of Festubert. The Battalion's War Diary entry for the 13th records "A few casualties sustained as a result of enemy fire on front line trenches and Estaminet Corner". The next day, the Battalion was relieved from the front line and moved back to camp. Probably during the night of the 13/14th, Gilbert was badly wounded.
He was evacuated from the trenches to a field hospital (Casualty Clearing Station) where army surgeons would have done all they could to save his life but without success. On the 20th, his platoon officer wrote to Catherine "Your husband was badly hit in the head on the morning of the 14th. The news of his death came through from 1st Canadian Casualty Clearing Hospital this morning."
After the War, Catherine moved away from the Stockport area and, in the 1920s, was living at 6 Churchill Grive, Liscard, Wirral. Gilbert's name is inscribed on the Stockport Memorial and the one at St George's Church. He is, almost certainly, the Gilbert Clarkson commemorated on the War Memorial at the hospital on Mill Lane, Wallasey.