The book is a story for children transitioning into a big bed and for parents who need to help them sleep through the night.
And if you head to the website set up to spruik Cass’s new venture – it appears Karl Stefanovic’s ex has taken the opportunity to take a cheeky jibe.
In the website’s ‘about us’ section which details Cass’s background along with fellow author Cara Campbell and illustrator Jennie Deane, eagle-eyed fans will see a reference to Karl.
‘By 35 Cassandra was mum to 3 children and her passion for children’s books, especially the art of reading them to children was reignited,’ Cass’s biography states.
‘But life was busy and she never got around to it until her husband left the marriage and Cass saw an opening to do something for herself.'
‘Well truth be told her close friend Cara Campbell shook her off and said let’s do a course,’ the bio continues.
It's been highly documented that Karl has now moved on - and is now engaged to shoe designer Jasmine Yarbrough.
‘Despite all that Cass is really only known in Australia as the ex wife of a breakfast TV host who happily stayed in the shadows for 21 years,' Cass's biography continues, before ending with this killer line:
‘A little known fact though is that Cass worked at the Today Show first.’
It's not the only reference Cass is reported to have made in her new book.
In it, she writes of a blanket called 'Bee Bee' which is apparently a reference to a baby blanket Karl carries around to this day.
Speaking previously to the New Daily, Karl said his divorce had been 'awful'.
'Hurts, doesn’t it? And I think the thing is you get accused … people say you don’t seem too emotional and it’s just rubbish,' the Today Show star said.
'I’ve been broken in the last year. I have been broken.
'Jasmine has been a light, and I wouldn’t have gotten through it otherwise.'