Precious was a whale that a ground sloth named Granny had kept as a pet.
A massive whale, Precious was the pet of a ground sloth dubbed Granny, though Granny's family thought her senile for mentioning Precious: indeed, Granny's family, namely Marshall, expressed that she was crazy for talking about her "dead pet". Precious was alive and in the oceans, where the whale grew to an enormous size.
Large, even for a whale, Precious was immense and the beloved pet of Granny, who was always seen throwing food into the ocean when she was near it, so that Precious might eat. Precious was loyal to Granny, so much that Granny could step inside the whale's mouth and commandeer her like a ship.
Precious' huge size was perhaps her more distinguishable trait. Her mouth, which was lined with rows of giant teeth, was large enough to accommodate an animal the size of a mammoth. Precious could also use her blowhole to blast jets of water to knock away any threats.