Margot Sunderland, director of education at the Centre for Child Mental Health in London, says the practice, known as “co-sleeping”, makes children more likely to grow up as calm, healthy adults. Sunderland, author of 20 books, outlines her advice in The Science of Parenting, to be published later this month. She is so sure of the findings in the new book, based on 800 scientific studies, that she is calling for health visitors to be issued with fact sheets to educate parents about co-sleeping.