He was educated at Gresham"s School, Holt, and from 1880 at the London Hospital (now the Royal London Hospital, where he held the Letheby scholarship.
After qualifying as a surgeon, Kelson held various hospital appointments. He was surgeon to the throat and ear department of the City Dispensary, became President of the Laryngological Section and Honorary Secretary to the Otological and Laryngological Sections of the Royal Society of Medicine and President of the Hunterian Society. In 1921, Kelson married Hilda Frances, younger daughter of Arthur West. Lane, of Ealing, but they had no children.
Only son or William Henry kelson Snr and Ann Maria perry.
He had 2 sisters Emily and Wilhelmina. He is the Grandson of Colonel Charles Kelson & GreatGrand Son of Doctor Thomas Mortimer kelson of Seven Oaks, kent.