The Secret Garden (centenary ed) by Frances Hodgson Burnett
After the death of her parents, Mary Lennox is sent back from India to live in her uncle's huge, gloomy house on the English moors. Mary is lonely and miserable until she stumbles upon her disabled cousin Colin, hidden away from the world by his troubled father. Together they discover the door to a secret garden, and open up a world of freedom and enchantment that they could have never imagined . . .