Sea Shells are the inhabitants of Sandman's Island.
The Sea Shells are all a brown or sandy color and they are all various shapes and sizes like shells, clams, conchs, mollusks, etc. Each of them have a pair of arms and legs and armed with spears.
The Guardians of Childhood
Unable to find to The Man in the Moon's question about keeping the children safe at night, Sandy heard what some of the creatures who lived in his island had to say. The Sea Shells told him that they have learned the children's joy and sorrow from the countless times they were held to their ears to hear the call of the sea. The sea shells also told him that Pitch's Dreams Pirates still roamed the night in search of sleeping children to hazard.
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related to Sea Shells.