Lauren Child: At home with Charlie and Lola
3 October 2015 Last updated at 00:05 BST
It is the moment Lauren Child's millions of fans have been waiting for - the release of a new Charlie and Lola book.
The last original Charlie and Lola story - one not based upon the popular television programme - was published five years ago.
In that time, among other things, Child has published a series of Ruby Redfort novels aimed at older children.
But the popular brother and sister duo are now back in a book about numbers, called One.
BBC News went to visit Child in her home studio to find out how she brings the characters to life.
Video Journalist: Alex Stanger
Footage courtesy of Lauren Child/Tiger Aspect