Character Analysis
Cissie-Mae and Ellie are Tom's younger twin sisters. They are often present in the background of domestic scenes, contrasting Tom's more serious and responsible temperament against their childlike playfulness and excitability.
There is way more attention to Tom and Polly Ann's relationship than to Tom's relationship with his sisters, but they seem like good kids overall. They want to know what Tom is doing, and sometimes they pester him, but they're also glad to help, like with difficult math and reading in his carpentry book (they continue on in school when he quits, so they're more literate). When Tom buys his new horses, Ellie helps him drive them home because she has a calm way around animals.
In one scene after Tom has put up his new barn, we see the whole family working together:
Polly Ann and the girls had put off milking till Tom could get home, so now they milked together in the lantern light in the new barn while Cissie-Mae went up into the mow and pitched hay down the chute and Ellie gently forked it in front of the cows. (58.6)
Cissie-Mae and Ellie's presence in the book emphasizes what a good provider Tom is because he has created a better life for them as well as for himself—and they also show that he may not have been so successful without the support of his family.