Millie and the Mermaid

When Millie is staying with Great Aunt Pearl by the seaside she decides she must learn to swim - everyone else seems to be having a great time in the water and she wants to join in. Great Aunt Pearl doesn't know how to swim either, so when Millie gets into the water with her armbands and rubber ring she must work it all out for herself. To Millie's surprise she sees a flash of silver in the water - a mermaid has come to help her learn to swim! With the mermaid's help Millie soon gains confidence and finds that she can swim - but was the mermaid really there?