Peter is a small green Billington E2.He is the #1 engine of the South Western Railway. Unlike Thomas,he has a single whistle and a trademark red lamp on his funnel. He is quiet,and apparently keeps to himself. Not much else is known about him.
Robert is a red LNER D3 with a short funnel. He is the #2 engine of the SWR, and is a few years older than Edward. He pulls light goods trains,and has constantly escaped scrapping. He has a very tall and deep whistle.