Rebecca is a Yellow SR Merchant Navy Class!
Despite her large size, Rebecca is shy and sometimes clumsy, but not afraid to stand up for herself and is not intimidated by the older engines. At times, she feels the need to be on the same level as the other engines, which can sometimes make her anxious or overhasty. But despite her insecurities, Rebecca loves to see the best in everyone and all her friends appreciate her kindness and enthusiasm. She also has the uncanny ability to work with Troublesome Trucks without trouble on the first try, something that confuses even the trucks themselves. Because Rebecca is so willing to see the good in others, she can occasionally be gullible, as shown when she fell for one of Diesel's tricks, but she is also very honest, willing to tell the truth if needed.
The Big Three (Does not speak)
Rebecca is based on the Southern Railway (UK's) "West Country" and "Battle of Britain" Class 4-6-2 Pacifics (Also known as "Light Pacifics" and Spam cans), originally designed by Oliver Bulleid, and 110 of these built between 1945 and 1951. The majority of these were constructed at The SR's Brighton Works, but 6 were built at BR's Eastleigh Works. Other than the names, "West Country" and "Battle of Britain" Classes were identical in every aspect. Due to some notable flaws with Bulleid's Original design, such as the troublesome "Chain Drive" Valve Gear and the infamous "Oil Bath", 60 "West Country" and "Battle of Britain" Locomotives were rebuilt between 1955 and 1961, becoming more conventional in design, which helped to reduce maintenance costs by about 60%. The last locomotives were withdrawn in 1967, but happily, 20 "Light Pacifics" Survived into preservation, with 10 each in u-nrebuilt and rebuilt condition respectively.
Rebecca is specifically based off the un-rebuilt "West Country" and "Battle of Britain" Classes, however, her tender is based off of the one carried by the rebuilt locomotives.