Katy Perry has fulfilled the dying wish of a 13-year-old girl from the Isle of Man by recording her a personal video message.

The American pop singer responded to a social media appeal on behalf of the family and friends of Sophie Birtles, who has a rare genetic disorder called Juvenile Sandhoff Disease.

Referencing one of her biggest hits, Perry said: "Sophie, I heard your story and wanted to say you are a firework, and I do love you."