She is a fan of skateboarding and adventures, and loves the feeling of soaring upwards and has happy memories of her deceased mum pushing her on a swing.

Katy's family consists of her dad, who is a doctor, Izzie, her stepmother, Clover, her sister who is described as sweet, kind and caring.

Elsie, her stepsister who she does not get along with, and her half siblings, six-year-old twins Dorry and Jonnie, and three-year-old Phil.

At the end of Helen's visit, she produces one of her possessions, a seahorse necklace, and decides to give it to Katy.

Her stepmother Izzie grounds her for sneaking out, and Katy is not allowed to go to the swimming pool with the rest of her family.

Mrs Burton, the woman who owns the garden, sees Katy fall and calls an ambulance.

Elsie Carr: The third sister, an awkward child at the beginning of the book, who is too old to play with the 'babies' and too young to be included in Katy and Clover's games.

Dorry Carr: (short for Dorian) An overweight boy who is the twin of Jonnie, he is often stereotyped to like eating.

Jonnie Carr (short for Johanna): A tomboyish girl who is the twin of Dorry, she is attached to a toy zebra chair named 'Zebby'.

Cecy Hall: A pretty and tidy girl, the daughter of their neighbour and a good friend of Katy's siblings.

Helen: Doctor Carr's old patient, who is unable to walk because of rheumatic arthritis years ago.