Edgar Stephen was a grandson of Sir Alfred Stephen who had been legal adviser to the Tasmanian government and later Chief Justice of New South Wales. The Stephen family produced many distinguished members of the legal profession, one of whom had worked with Wilberforce to secure the abolition of slavery. He attended the Sydney Grammar School prior to the University of Sydney from which he graduated Bachelor of Medicine in 1902. He spent his first postgraduate year as a resident medical officer at the Sydney Hospital and the second at the Sydney Hospital for Sick Children, as it was then known. In 1905 he went to London and became a house physician at the Brompton Hospital for Diseases of the Chest. As was customary in those times, after his return to Sydney, he entered general practice in Ashfield. Like most doctors he did his rounds of his sick patients in their homes by horse and sulky.

On the outbreak of war in 1914 he enlisted in the Australian Imperial Force and served with 6 Field Ambulance in France and later with the Australian General Hospital at Rouen. He was promoted to major and appointed to the medical board which assessed the fitness of volunteers for flying duties. On his return to Australia he continued this interest and examined candidates for civil aviation for twenty years. While in France he had met his future wife, Miss Whiteman, who was an army nurse and they were married in London before he returned to Australia.

Edgar Stephen was appointed as an honorary relieving assistant physician to the Royal Alexandra Hospital for Children and this hospital was his major interest until he retired as the senior honorary physician in 1938. He had a great understanding of small children and his ward rounds were a demonstration of this. These rounds were famous, entertaining, thorough, long and very instructive to the undergraduates and postgraduates who accompanied him. His quaint idiom and joking approach gained the child's confidence and ensured that his advice to the mother was better remembered. He held the appointment of clinical lecturer in medical diseases of children of the University of Sydney from 1926 to 1938 and accordingly gave the lectures to medical students who spent a term of their fifth year at the hospital. These lectures were also famous as he believed the duty of a lecturer was to stimulate his audience and keep them awake. This he did with the most unexpected, whimsical and sometimes very funny remarks. He retired from the active honorary medical staff of the hospital when he reached his sixtieth birthday but continued to serve in outpatients or wherever needed during the war years. In the 1930s many general practitioners experienced his skill with the sick child as medical students, as resident medical officers or as postgraduate students at the Royal Alexandra Hospital for Children and he became one of the first, if not the first, consultant physician in Sydney to restrict his work to children.

He had many other activities. He was a member of the council of the British Medical Association (NSW branch) from 1932 to 1941 and was president in 1936. He was a member of the Postgraduate Committee in Medicine for many years and was made a life member of this committee. He was a member of the New South Wales Consultative Committee for the Physically Handicapped which was mainly concerned with the management of poliomyelitis. For many years he was a member and later became president of the Bush Nursing Association. He was a consultant of the Far West Children's Nursing Home at Manly and investigated and treated many of its inmates in the Eastern Suburbs Hospital, to which he was the honorary paediatrician. In 1938 he was invited to become a foundation Fellow of The Royal Australasian College of Physicians.

During the 1939-45 War and for several years afterwards he was a member of the medical board which sat at Victoria Barracks and later at Marrickville. He was also interested in those members of the Navy with whom he came in contact. He would speak to naval officers from other countries whom he saw in the streets and would invite many of them to his home. He would maintain a correspondence with many of them after they returned to their homes and continued to do this right up to his death.

Edgar Stephen enjoyed social intercourse. He was much in demand as an after-dinner speaker and could produce an amusing extempore speech to suit the occasion. He enjoyed presiding at meetings and when he did so the meeting went smoothly with few dull moments. He had numerous friends both within and outside the profession and never failed to write a letter of congratulations or condolences according to the circumstances. Beneath the whimsical, vivacious speech and chatter, which could seem flippant and superficial, he had a great humility and a deep religious faith. He was a regular church-goer and was a member of the Anglican Synod until his death.

Edgar Stephen was a gifted children's doctor and a humble, caring physician who set a standard of practice which has been a stimulus to those who followed him.