Morph is the trusted sidekick and pet of John Silver. Morph is known for being quite mischievous and has caused trouble in the past. He displays a liking to Jim Hawkins, the protagonist, and is able to assist him with his morphing powers. While he initially follows Jim only due to Silver's orders and later due to the circumstances of them fleeing the ship, when he has the chance to return to Silver, Morph is frightened by his master's behavior and stays with Jim instead when Silver orders him to come. He returns to Silver after he saves Jim, but is shown to have grown so fond of the boy that he cries himself into a puddle in Jim's hands. This display has Silver get Morph to stay with Jim rather than break his heart.
Morph first appears when Jim is in the kitchen and tries to eat some soup. Morph is in the form of the spoon he uses and shocks Jim when he tries to eat with him. Silver later assigns Morph to watch over Jim and Morph plays tricks on the boy, such as stealing his boots. However, the two also have a good time together such as after the confrontation with Scroop where they make fun of Scroop with Morph taking on Scroop's form to add effect. Morph's antics later lead Jim to discovering the truth about Silver and the mutiny.
He later plays a trick on Jim by transforming into the Map and thereby revealing that the real map was still on the ship, which the crew had stolen. When Silver talks with Jim, trying to bribe the map from him, he calls for Morph to come with him but Morph stays with Jim after seeing for the first time his master's other side, and hearing him say that he cared about only one thing: Flint's treasure. This most likely broke Morph's heart because up until that point he thought that he really mattered to Silver. Morph stayed with Jim for most of the adventure following that, aiding him in battling Scroop and watching as he fixed Flint's ship. When Jim's life was in danger, Morph indirectly saved him by alerting Silver to his predicament. Following this, Morph returned to Silver's side, but continued to aid Jim by trying to help lift his makeshift solar surfer so he could save the ship.
When Jim saved everyone, Morph turned himself into fireworks to celebrate and smiled with Silver as they saw Jim getting the chance at a future in the navy for his actions. Morph accompanied Silver as he prepared to flee, but was reluctant to do so, with Silver insisting they had to go. Jim found them, but let them escape. When Silver offered Jim the chance to join them, Morph turned himself into a captain's hat and landed on Jim's head to help emphasize this idea, but Jim refused. Morph, having grown very attached to the boy, was so upset he burst into tears and cried himself into a puddle in Jim's hands. Jim promised they'd see each other again, even though it was unlikely, and Morph sadly returned to Silver who, seeing how upset Morph was, asked him to stay with Jim and look after the boy for him. Morph was excited by this and happily agreed before watching Silver leave with a surprised Jim.
He later greeted Jim's stunned mother and when the Benbow Inn reopened, turned himself into a pair of scissors to cut the ribbon. He is last seen during the party watching over Doppler and Amelia's children, making his eyes grow very big for the job. When one gets upset, Morph turns himself into a rattle for the little boy to use.
- In the original Treasure Island novel, Silver's pet was a parrot that he named after Captain Flint, whom he had served under, to mock him.
- Morph comes from the planet Proteus I. Proteus was a shapeshifter in Greek Mythology, so Morph's homeworld's name is a reference to his own shapeshifting powers.
- He bears some resemblance to Morpholomew from Lilo & Stitch: The Series in form, color, and that they both have shapeshifting powers.
- He also resembles Ditto from the Pokémon franchise as they both are pink and capable of shape-shifting.