They have different jobs on the railway and this special coach is Donald's to pull everyday on his own branchline while Douglas just does regular jobs on the railway.
In fact, Douglas argues with Donald once that he wants to pull this coach and doesn't like sleeping in a shed with animals by the side because he doesn't like animals…
But when Donald can't do his job, Douglas gets to do a job he's always dreamed of: pulling the coach instead of his twin brother. After doing so, he boasts to all of the engines about this and Donald as well!
- This coach is reuesed form a Knapford Express Coach.