Kate Middleton is the first royal to ever take part in CBeebies Bedtime Story.
And the Duchess of Cambridge will help send children to sleep with an appearance on the show as she reads a story to her own three children.
Kate, 40, will follow in the footsteps of Tom Hardy, Reece Witherspoon, Ryan Reynolds and Dolly Parton for the show.
Looking at home and sitting crosslegged in jeans, and a roll-neck sweater Kate will read an abbreviated version of The Owl Who Was Afraid of the Dark.
The story, a favourite of Kate's when she was younger, talks about an own who is scared of the dark and perfectly marks Children’s Mental Health Week Sources
George, 8, Louis, 3, and six-year-old Princess Charlotte will all feature on the show which was filmed at Kensington Palace with her.
A source said: "The duchess personally selected the book because it chimes with children's mental health week.
"The theme of the week is growing together and the book is about an owl who overcomes their fear of the dark.
"She enjoyed reading the book as a child and reads it to her three children now."
The Owl Who Was Afraid of the Dark follows the story of Plop, a baby barn owl, who is helped by others to grow in confidence and overcome his fears.
The programme will air at 6.50pm, Sunday 13 February and it will remain on BBC IPlayer.
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