Mermaid - Cerrie Burnell

Once there was a boy called Luka, who lived in a town beside a deep
silvery sea.
Luka longed to splash in the surf and dive beneath silver-bright
waves, but he couldn't swim.
One day, Luka sees a girl gliding through the waves, dipping and
soaring like a fish. Luka has never seen anyone swim so well. Sylvia
teaches Luka how to swim, and that night, Luka dreams that Sylvia
is a mermaid and they have a beautiful underwater adventure
visiting the mermaid palace.
And when Luka starts school, Sylvia is there! The other children
crowd around her to ask why she's in a wheelchair, and Luka tells
everyone that it's because Sylvia is a mermaid.
Luka knows that to him she will always be a mermaid and they will
have a thousand more adventures together.