Sammy the Sea Serpent

Sammy and Tommy are half sea serpent like their mother and half dragon with wings like their father. This series starts with how twin sea serpents Agnes and Horace, along with Eric the dragon, survive the Ice Age before waking up in the 21st century. They all live on an uncharted island protected by friendly natives and a magic cloaking spell that makes the island invisible. They also share the island with other prehistoric survivors of the Ice Age.Tommy might be 3 years older, but Sammy is clearly the leader when they embark on their various adventures. Their many adventures start in book 2 and includes a group of research scientists, a notorious big game hunter, pirates and pirate treasure.