sentences:  In 2016, Dot retires from her job in the launderette and finds a mixtape made many years earlier by Heather and Shirley, featuring their voices and several Christmas songs.Heather was introduced in June 2007 and was originally only meant to be a guest character, but Fergison's contract was extended to six months after the character proved popular.She was introduced as the sidekick of Shirley Carter, played by Linda Henry.