Ellie did indeed think she was going for a sleepover; four days after the incompetent "Services 4 Children" ripped her away from her grandparents, JG and BB phoned them up to gripe about Ellie's behaviour and that she thought it was only a temporary sleepover.
Services 4 Children were absolutely cruel. At first they were only supposed to be overseeing YD's return, then they decided Ellie should return too. It was supposed to be a slow process to ease Ellie in to the change, but it ended up happening in a few weeks. If I remember rightly it was supposed to happen slowly over a year, then it was reduced to by the end of 2013, then the end of November after a sleepover, then the 9th of November. There was no sleepover, it just happened suddenly. S4C didn't even allow the grandparents to say goodbye; the grandparents dropped Ellie off at school one morning as normal, then JG and BB came to pick her up and that was that. Ellie had no idea. S4C forbade contact between Ellie and the grandparents for 4 weeks to get her used to it.
S4C insisted that the grandparents should not discuss the move with Ellie, although the grandparents wanted to be honest and open. Ellie was terrified every time S4C visited and would try to hide. She had nightmares about them taking her away and began to wet the bed. S4C paid no attention to Ellie's loving bond with her grandparents and her deep wish to stay with them, and forced her to live with JG and BB despite their belligerence and incompetence (including JG not bothering to take time off work for YD's introduction).
As well as failing to prioritise Ellie's wishes, then failing to ease her in slowly (effectively sending Ellie to live with hostile strangers), S4C also failed to contact people who had previously worked with Ellie, so that they didn't have a full picture of what was going on.
No wonder people are terrified of social workers, when they behave like this - suddenly ripping children away against their welfare and wishes, without telling them what's happening and without allowing them to say goodbye to their loved ones.
S4C should not be allowed to practice.