Exhausted parents from around the world are singing the praises of a "miracle" book which promises to put even the most restless child to sleep in just minutes.
The Rabbit Who Wants to Fall Asleep has become Amazon UK's top selling book, and has already been translated into seven different languages.
It tells the tale of Roger the Rabbit, the Sleep Snail and Uncle Yawn on a quest to help the rabbit go to sleep.
If reviews on Amazon are anything to go by, the book seems to be successfully sending children off to dreamland in bedrooms everywhere.
"I'm actually speechless! I'm sat here waiting for someone to pinch me," one happy purchaser wrote. "Bedtime just went from taking 2-3 hours to taking 12mins. We made it to the middle of page 2."
"This is magic! For the last year our 4-year-old daughter has dodged sleep, finding various reasons to come into our bedroom sometimes past 11pm," commented another. "On the first read, she fell asleep just before the end, the second time we got half way through the second page - would highly recommend!"
The 26-page book uses psychological and positive reinforcement techniques to help children fall asleep, and includes instructions for parents on how to read the book.
Parents are advised to read in a calm voice, are told which words to emphasise, and when to yawn during the sentences.
The book was written by Swedish behavioural psychologist and linguist Carl-Johan Forssen Ehrlin who says it is the "verbal equivalent of rocking a baby to sleep".
"This is an innovative and groundbreaking type of bedtime story that uses sophisticated psychological techniques," Forssen Ehrlin told UK's The Independent.
"These are formed in a way to help the child relax, fall asleep faster and sleep calmer every night. The tale gives suggestions to the child's unconscious mind to sleep."
Forssen Ehrlin is so certain of his book's powers that he played recordings of the text to his own baby while he was still in the womb. The little boy still falls asleep to the story now.
But, as with any "miracle" product, not everybody is convinced. Some Amazon reviewers have complained the book was too long or that their children found it boring.
"Not sure I agree with all the hype," said one disappointed purchaser. "I've had issues with my 2-year-old sleeping since he was 1, I found the book very long and he got distracted!"
However Alison Forrestal, Amazon UK's Director of Books and Entertainment Media, praised the book, saying it was the first time a self-published book had become the number one best-seller print product.
"This book has been a word of mouth phenomenon," she told UK's The Telegraph.
"Carl-Johan took the opportunity to independently publish and has now reached parents and children all over the UK.
"This is the first time an independent author has taken the number one position in our print books chart. It's a great achievement and we, like many families across the UK, hope there are many more books to come."
Those wishes just might come true, with Forssen Ehrlin planning to next write a children's book about toilet training.
If he then focuses on books about eating vegetables, tidying bedrooms and not fighting with siblings, Forssen Ehrlin may well make parental nagging obsolete.