Kelly was the first member of The Pack to be purchased, having originally belonged to Miss Jenny's father. As such, he is the oldest vehicle in the company, and the wisest. He works happily on the various construction sites and is known to keep everyone cool, collected, and content!
Kelly is a prime example of how wisdom comes with age, and is very conscious on the welfare of those around him. He is very close friends with Isobella, and is Miss Jenny Packard's most trusted machine. He is often a voice of reason, and guides the younger members of the Pack to make the right decision. He used to have a fear of strong winds, but he conquered that fear when he rescued Isobella from teetering on the side of a wall.
Kelly is painted navy blue with a cream crane arm and red lining. His wheels are navy blue with red lining. He has the number "17" painted on his sides in white.
- Season 1 - Harvey's Goods Train, Waterworks (cameo), Scruff the Scrapper (cameo), and Fergus and the Small Engines
- Season 2 - Disappearing Diesel (cameo), Haunted Henry's Forest (cameo), Breakdown Butch, Jack and the Quack, Sidney Gets Lost, Sodor Day (cameo), Pile Driver Pedro, Pedro Deep Down, Truck Trouble, and Ministry (cameo)
- Kelly is one of the machines whose silhouette is pictured on the Pack's logo.
- Kelly has the same horn sound as Madge.