Sunshine is Captain Star's seventh tug, a small 'harbour switcher' who is used for a wide variety of tasks around Bigg City Port. Sunshine was introduced in the pilot episode of the same name. He has many capabilities that range from the towing of barges to liner docking operations, in his first assignment from the Star Fleet, he was pushed by evil Z-Stack Zorran who caused the whole thing to be a disaster. Like the rest of the Star Fleet, Sunshine is based on the tugs of San Francisco waters from the 1920s.
Sunshine can be occasionally cheeky at times, but he is very strong willed nethertheless. He is quick-witted and takes action swiftly without hesitation (usually).
Sunshine also can figure things out very quickly, as in "Jinxed" where he points out that each of jinxed tug Boomer's unfortunate mishaps occurs right after Ten Cents sounds his steam hooter, suggesting a cause-and-effect relationship. On the subject of whistles, Sunshine's is middle-to-high pitched and has a distinct 'whooping' sound which could best be described as 'upbeat', suiting his personality and name.
Sunshine works mainly with Ten Cents, the Star Fleet's first and larger switcher. They have shared many adventures, almost to the extent that it is impossible to imagine one without the other. They are both best friends.
Sunshine has a rather soft Newcastle (or Geordie) accent and (most of the time) he whistles when he speaks, because he is missing some of his front teeth. Sunshine's character reflects that of Percy from the sister series, as the youngest.