Heihei

Heihei is a rooster that unintentionally joins Moana and Maui on their journey across the ocean.

Personality
To put it simply, Heihei is incredibly stupid. He is usually unaware of his surroundings and, as a result, places himself in varying degrees of danger without much notice. He is accident-prone and easily distracted, which makes him a complication in Moana's journey, though she'll work to protect her friend and loves him unconditionally, nevertheless.

Though his actions would strongly imply otherwise, Heihei has some level of awareness that is seen on rare occasions. For example, he was able to differentiate his island home to the blankness of the sea, and additionally deduced that he and Moana had ventured passed Motunui's reef (which is against the village law because of the dangers within the sea). This causes Heihei to go into panic and is perhaps the only instance in which he showed signs of mortality and fear. During the climax, he proved that he understood the importance of Te Fiti's heart to Moana, and actively risked his life to help her maintain it when it nearly falls into the ocean during the second battle with Te Kā.