Dorothy Casey is Zachary and Ellie Clemens’ daughter. Together with her parents, she helps the Caseys on the ranch. The Clemenses are extremely poor, which is shown, when Lily first gets to know the family:
“They were living in an outbuilding on a corner of the property. Mom considered them beneath us because they were dirt-poor, so poor that they used paper for curtains.” (p. 44, ll. 12 - 15)
Lily likes Dorothy, since she does not baulk at hard work
Dorothy […] knew how to roll up her sleeves. She was a big-boned young woman with ample curves, handsome despite a wart on her chin. Dorothy knew how to skin a cow and trap rabbits, and she tilled the vegetable garden the Clemenses had fenced off, but she spent most of her time at the big kettle that hung over the fire pit in front of the shed, cooking stews, making soap, and washing and dyeing clothes she took in from the townspeople in Tinnie (p. 44, ll. 18 - 25)
It is Dorothy, who finds the expensive Great Danes shot dead. When Adam Casey wants to shot Pucket because he killed the dogs, Dorothy prevents him from doing so, telling the Caseys about her brother:
“When her family was living in Arkansas, she went on, her brother had killed someone in self-defense […]. My brother’s dead, and we ain’t got two nickels to rub together […] because a stupid argument over a damn game of horseshoes got out of hand.” (p. 45, ll. 19 - 27).
Dorothy, who is “a few years older” (p. 52, l. 8) than Buster, marries the 16-year-old in 1918. Dorothy is going to manage the ranch
during the next years, which is shown when Lily returns to the ranch after her time in Red Lake:
“Buster and Dorothy […] lived in the new wing of the house, and it soon became clear to me that Dorothy was more or less running the place. She oversaw the kitchen, bossing Lupe around something fierce, and handed out the daily work assignments for Buster, Apache, and even Mom, Dad, and Helen.” (p. 66, ll. 21 - 25)
Dorothy does her job very well and is able to get the most out of the ranch by working very hard and making the others work hard, too: “[…] The place looked well run, the fences in repair, the outbuildings freshly whitewashed, a new clapboard wing on the main house, a big supply of split firewood neatly stacked under the porch rood, even a bed of hollyhocks and sunflowers” (p. 66, ll. 11 - 14).
Furthermore, Dorothy is able to assert herself
, even in front of Lily’s mother, Daisy Mae:
“Mom’s plan was to send Helen to the Sisters of Loretto […] but Dorothy argued that all the earnings from the ranch needed to be reinvested in machinery to raise crop yields” (p. 67, ll. 6 - 9).
Dorothy is a person, whom Lily really respects since she is a lot like her.