The Kawartha Lakes Railway is an “internal short line” that the CPR created to handle trains on their Havelock & Nephton subdivisions in 1996. After the United Railway Trust merger, the CPR transferred ownership of their east of Toronto trackage to the LT&L, including the KLR.
The KLR is not exactly a traffic-laden shortline; there are a few quarries along the Nephton subdivision, plus a small handful of industries in Peterborough (some on abandoned CNR trackage that was sold to the CPR to retain service), but there is enough freight to occupy 7 locomotives. When the KLR was a CPR subsidiary, it leased all of its power from the CPR, and those leases survived the merger; this included a few locomotives in the old CPR Multimark scheme, and those have been lettered for the KLR.