It's written by the author of 'Chocolat', it's not so much a sequel as a return to the lives of the main characters. This is a much darker book than Chocolat, with more 'peril' and darker magic.
If you haven't tried these titles I highly recommend them. If you have only seen the film 'Chocolat'- it really goes against the grain to knock Johnny Depp and Juliet Binoche - but it pales in comparison to the book.
(Apparently in the US it has been published as 'The Girl With No Shadow'. I do think 'The Lollipop Shoes' is much more tantalising:)