Rosie is a lavender tank engine who works alongside Thomas, and idolises him, this can rather aggravate Thomas on all occasions.
- Season 5:
- Season 7:
- Season 14: Henry Gets Stumped (cameo), Hiro and the Heat Wave, Merlin the Magical Engine (cameo), Dirty ‘Arry (cameo)
- Season 15: Roundhouse Roulette
Rosie is a SR USA Class 0-6-0T; Rosie, however, has a taller funnel then the rest of the class, the SR USA Class 0-6-0T's were used as dockyard shunters, replacing the LB&SCR E2 locomotives which are Thomas' brothers.