Daisy is a diesel railcar, who came to the North Western Railway to work on the Ffarquhar Branch Line after Thomas' accident at the Ffarquhar Stationmaster's house. She currently works on the Harwick Branch Line with Ryan, and looks after the passenger trains.
Daisy was built by Metro-Cammell in 1960, and was sent to work on the Ffarquhar Branch Line after Thomas' accident at the Ffarquhar Stationmaster's house. Upon her arrival, Daisy proved to be lazy, rude and snobbish. She spoke rudely about Annie, Clarabel and Henrietta, refused to sleep in the engine sheds on the grounds that it was "smelly" and refused to pull trucks. During her first day on the job, she got into an argument with her Driver and the station staff when she had to pull the milk van on her first run, claiming it was "bad for her swerves". As the train was already late, Daisy was allowed to leave the station without the van, much to her delight.
Daisy later called Toby a coward for wearing cowcatchers and sideplates, believing that all it took to get an animal to move was a toot of her horn and looking them in the eye. However, when she came across a bull grazing on the track, Daisy became frightened and was unable to move him, so Toby was called out to move the bull along.
When the Fat Controller found out about Daisy's laziness, he threatened to send her away if she misbehaved again. Daisy was sympathetic, and agreed to allow Toby to teach her his ways. Under Toby's wing, Daisy became a hard-working and reliable engine, and when Thomas returned from the Works, she began assisting him with the passenger duties. (RWS; Branch Line Engines)
When Mavis came down to Ffarquhar and began complaining about Toby, Daisy convinced her that diesels could do anything better than steam engines. This was not exactly the best move on Mavis' part, as Daisy knew nothing about trucks. (RWS; Tramway Engines)