Carl-Johan Forssen Ehrlin
Carl-Johan Forssen Ehrlin's new book, The Rabbit Who Wants To Fall AsleepCarl-Johan Forssen Ehrlin

Exhausted new parents rejoice! A Swedish behavioural psychologist has written a book which he claims is guaranteed to put your child to sleep.

Carl-Johan Forssen Ehrlin's new book, The Rabbit Who Wants To Fall Asleep, has shot to the top of Amazon's best sellers list with the claim that "I can make anyone fall asleep", as the boast on the front page reads. Using psychological techniques, the book is "the verbal equivalent of rocking your child to sleep... I help the child focus on relaxation and become part of the story," Ehrlin explains.

Roger the Rabbit is the book's main character and is accompanied by Uncle Yawn, the Heavy-Eyed Owl, and the Sleep Snail on his quest to get to sleep as they urge him to "think slowly, breath slowly and calm, slow and calm." Another sentence reads: "let your whole body be heavy, so heavy it feels like it falls... just like a leaf, that falls down, slowly down, down... Your eyelids are so heavy."

Ehrlin told the Telegraph: "I had written books before about leadership and personal development using these techniques but I got the idea for a children's book while I was driving on a long journey with my mother and she fell asleep, and I got the idea of how I could use my methods to help children relax.

"When we stopped I wrote it all down on a napkin but it took another three and a half years to come up with the perfect story so that all the techniques were used in the correct order. It helps the child to focus and makes them a part of the story so that they fall asleep along with the rabbit."