The narrator decides to give us a chapter about two of the youngest members of the extended March family – Daisy and Demi, Meg's twins.
The twins are precocious and in danger of being spoiled. Daisy begins trying to sew like her mother when she's only three, and Demi starts learning the alphabet at the same time.
Mr. March teaches his grandson the alphabet using a game in which they make the shapes of the letters with their bodies. It's sort of a "YMCA meets Sesame Street" kind of thing.
Demi is also very interested in mechanics and physics – he even tries to make his own elevator out of a basket hung over a chair. Daisy, the unfortunate passenger in this elevator, gets her head smacked against the chair a lot.
The twins mostly get along well, even though their personalities are really different. Daisy is an unnaturally sweet, quiet girl interested in all things domestic. She reminds her grandparents of Beth, the daughter they lost.
Demi is completely different from Daisy – he's very inquisitive and mischievous.
One day Demi asks his grandfather what makes his legs move, and they end up having a conversation about how the mind works, and how human beings are related to God. Grandma – that's Marmee – is worried that this is too much for the child to understand, but Mr. March says that if he's old enough to ask a question, he's old enough to get a true answer.
Demi is also constantly causing mischief. One day Meg tries to stop him from eating too many raisins, but when she promises later in the day to play any game he wants, he chooses "eating all the raisins."
Jo, called Aunt Dodo, plays a lot with both of the children. After Mr. Bhaer starts hanging around, she neglects them. They're sad that she doesn't pay as much attention to him, but they both like Mr. Bhaer, who is good with children.
Mr. Bhaer always asks for Mr. March, and the two men talk about philosophy, but nobody is deceived; they all know that he's really interested in Jo.
One day, Demi puts Mr. Bhaer and Jo in an awkward position; he asks if big boys like big girls, the way that he likes one of the little girls he knows. Mr. Bhaer blushes and says, well, he thinks sometimes they do.
Jo rewards Demi for this awkward question by giving him a slice of bread and jelly. Demi doesn't know why, but he's happy to take it!