Yorkiegirl ... your DD sounds like she is at the perfect age to give up the dummy. This is what my SIL did with her nearly 3 year old: They wrote their usual letter to Father Christmas in November and as a post script they enclosed Dniece's dummy "For FC to give to a baby who needs it".
For a couple of nights DN cried and raged at FC saying she didn't like him and wanted her dummy back but then she was fine about it.