Jessie fell ill and in 1913 she moved abroad for a period to convalesce. Their older son Arthur joined the army, became a Second Lieutenant, and was killed in action in Flanders in April 1915: he was eighteen.

The Guardian dated April 19th 1915 reported: "Lieutenant A. C. Brickwood, York and Lancaster Regiment, son of Sir John Brickwood of Portsmouth, died in hospital at Boulogne on Thursday night. He was taken ill a few days ago at the front, where he had been fighting in the trenches for some time."

Younger son Rupert Redvers later became 2nd Baronet Brickwood on the death of his father: he became a Squadron Leader in the Royal Auxiliary Air Force in the Second World War, and was a Director of Brickwoods.

John and Jessie returned to England, but Jessie died in 1917.

John later remarried to Isabella Janet Gibson Gordon: they had four sons - Kenneth, Geoffrey (who was captured fighting in Crete in the Second World War, imprisoned in Austria, and later emigrated to Australia), Bruce (who also retired to Australia), and Basil Greame (who was in the RAF, and later became 3rd Baronet on the death of Rupert Redvers).

Sir John pursued his business and interests - literature, archaeology, astronomy, architecture and Egyptology - and was made Baronet Brickwood of Portsmouth in 1927: there are four photographic portraits of him by Bassano in the National Portrait Gallery, London, all taken in the 1920s, at Portraits of Sir John

Around 1930 he purchased Cadlington, Horndean where he died in February 1932 aged seventy nine.