Katie and the Snow Babies (Mermaid S.O.S. Series #8)

The evil mermaid Mantora has stolen six precious Snow Diamonds from Ice Kingdom, and it's up to the Arctic Mermaids to find them! In Katie and the Snow Babies, the mermaids discover that a baby polar bear and walrus have gone missing, and Katie and her friends vow to find them. Along the way, the mermaids gets some help from the chief walrus in figuring out Mantora's clue to where the next Snow Diamond is hidden.