Dewey, Squirt and Tadpole Blue are triplets, and the younger brothers of Lagoona Blue. They appear in the Monster High Diaries book Lagoona Blue and the Big Sea Scarecation, and the TV Special Great Scarrier Reef
In the English version, Dewey, Squirt, and Tadpole are voiced by Piotr Michael. In the Latin American Spanish version, Dewey is voiced by Emilio Jacob, Squirt by Jared Mendoza and Tadpole by Ángel García.
The three brothers are typically active and mischievous young boys, who love to stay active and are always looking for something to do. They look up to Lagoona and are always trying to get her to join their games.
As water monsters they have scaled skin, one as pale blue scales, one green, the other a more aqua color. They have fish fins at the sides of their lower arms. They also have redish-brown eyes, and three toed feet.