My half-brother Paul Holmes, who has died aged 76, was a child and adolescent psychiatrist and a renowned psychodrama specialist.

Paul dedicated his life to mental health and the therapeutic benefits of psychodrama, a method using role play to help individuals confront emotional issues. His books on psychodrama and group therapy, including The Inner World Outside: Object Relations Theory and Psychodrama (1992) and Psychodrama Since Moreno (1994), are regarded as essential texts.

Born in London, Paul was the elder son of Mary (nee Refoy), an author, schools inspector and botanical painter, and Brian Holmes, professor of comparative education at the Institute of Education, University of London. After leaving Whitgift school in Croydon, Paul earned his medical degree and PhD in physiology at University College Hospital in London.

He became an adolescent and child consultant psychiatrist in Wandsworth, based at the Margaret Press assessment centre and Battersea child guidance unit. After retiring to Sussex, where he and his husband, Weston Tulloch, created a beautiful garden, he frequently returned to London to visit friends, explore galleries, and dine out.

In 1998 Paul played a key role in establishing Family Futures, an innovative adoption support service drawing on his expertise in adoption, trauma and the use of psychodrama. As the agency’s first child and adolescent psychiatrist, he took up cases and continued his association while working at the Whitehouse Child and Adolescent Service in Brighton, which was modelled on Family Futures.

Paul collaborated with many leading figures in his field. He worked with therapists and educators in eastern Europe, Latin America and Russia. His commitment to global mental health reflected his desire to share knowledge across borders. He often noted that he followed in the footsteps of our father, who also worked in Russia to advance comparative education.

Known for his sociability and warmth, Paul connected deeply with troubled adolescents. He took pride in being an iconoclast, once being one of the few doctors formally warned for his indecipherable handwriting. He was a man of immense intellect and his passions included garden history and design.

He is survived by Weston, whom he married in 2016, and two siblings – my brother, Andrew, and me.