I remember most of the story and the names. In brief the main character is a girl named Alison who has a younger brother (Chrissy?). Their parents are divorced and Alison and Chrissy live with their mother. Mum subsequently becomes ill and has to have a long spell in hospital. A & C have to go to live with their father, who is remarried with a step daughter (Rosa?). Alison is determined not to get on with her new stepmother and stepsister but slowly acknowledges their value and accepts the benefits an extended family can bring.
The book explores issues such as class difference, image, reconciliation, family bonds etc.
I really enjoyed it when I was younger and would love to read it again. It comes across as an Anne Fine type book but I haven't recognised it in her book lists.
Does anyone know what this book is?!