Portrait of the artist as a young man

Had the artist Rex Whistler not been killed in Normandy in 1944 at the age of 39, in what direction would his great talent have gone? It is futile to speculate, write Hugh and Mirabel Cecil, the authors of this sumptuously illustrated new biography. But many did. Cecil Beaton thought he would have become another Turner. My mother Caroline Paget, his greatest love (but who loved him without the intensity that he loved her), thought he would have become one of the greatest portraitists of the 20th century and, relishing new ideas in stage design, also one of the most famous designers of his day. All his friends thought that soldiering had changed both him and his art. His work, so often fanciful, rococo and gorgeous, became increasingly darker and more naturalistic.

Rex (he was killed five years before I was born, but he was talked about with so much love all through my childhood that I feel we are on Christian-name terms) was born in 1905, into the respectable middle class, no relation to the celebrated James McNeill. Even before he left school at Haileybury, a remarkable talent for draughtsmanship, along with imagination and humour in its execution, had already become apparent in his work.

After a false start at the Royal Academy, he studied at the Slade, where the redoubtable Professor Tonks became his teacher and mentor. Here he made friends with the exotic and terminally aesthetic Stephen Tennant, who introduced him to the smart, bohemian world in which he was to move thereafter, and where he was in his element. Through Stephen, he met the writer and mystic of Wilton, Edith Olivier, 30 years older than he was, who became his greatest friend and confidante, and whose adoration of him sometimes appears more than maternal. But she understood him, as his own mother never really could.