Book excerpt: Shiraz, a kindhearted young girl growing up in Tehran, has a miserable life at home with her stepmother and stepsister, who treat her like a servant. When the wind blows Shiraz’s ball of wool into the garden next door, she spends the day helping and caring for the old lady who lives there, with miraculous results. Then her stepmother sends her own daughter off on the same mission . . . but will the results be the same?