imagining his homecoming.

Night after night in my bunk I figgered ... maybe Grampa or Granma'd be dead, an' maybe there'd be some new kids. Maybe Pa'd not be so tough. Maybe Ma'd set back a little an' let Rosasharn do the work. I knowed it wouldn't be the same as it was.

But when Tom returns home, the farm is deserted and the house is destroyed. He catches up to his family on their journey to California where they believe they will find jobs and a better life. As Tom sees his mother for the first time in years, he notices that she is the source of the family’s strength.

Tom stood looking in ... She seemed to know, to accept, to welcome her position, the citadel of the family, the strong place that could not be taken.

Although Ma Joad is the bastion of their individual family, she is also the first character to see the wisdom of expanding their horizons beyond immediate relatives to include the larger community. In the Dust Bowl, families like the Joads have been driven off their land and lost everything. Small families did not have the strength or the resources to fight for their way of life. Ma Joad realizes that if they became one large force, they could prevail.

She came near to him then, and stood close; and she said passionately, "Tommy, don't you go fight in' 'em alone ... I got to thinkin' an' dreamin' an' wonderin'. They say there's a hun'erd thousand of us shoved out. If we was all mad the same way, Tommy—they wouldn't hunt nobody down—"

Tom adopts this way of thinking when he becomes a labor organizer. The workers are empowered when they belong to one collective unit. The “family” is expanded to incorporate the community.

The novel ends with a powerful image of this stronger, communal family. Tom’s sister, Rose of Sharon, has just delivered a stillborn child. When she and Ma Joad encounter a starving man and his son, she saves him by giving him the milk her baby would not be using.

Rose of Sharon loosened one side of the blanket and bared her breast. "You got to," she said. She squirmed closer and pulled his head close. "There!" she said. "There." Her hand moved behind his head and supported it.

She nurses the stranger as though he is her child. It is the ultimate act of “family”—providing nourishment and care like a mother, symbolically adopting this member of the larger community as a part of her family.

Ma Joad continually expresses the idea that there is strength in family.  One clear example of this is in Chapter 16 when Tom suggests that he and Jim Casy stay behind to get the truck fixed while the others go on.  Ma steadfastly refuses to go with out Tom.  She says that the family is all that they have left in the world and she doesn't want to break it up.  Another example is in Chapter 18 when Ma reveals that Granma had died before the group crossed the desert, but rather than reveal that and jeopardize the family's chances of making it across the desert to their destination in California, she lied at the border station and held Granma's body all night long.  Many times Ma tells Tom that it is important that the family stay together each time expressing the idea that they only have each other.

Tom expresses his realization of the need for the family to work together, too, when he curbs his anger so that he won't get in trouble and be sent away.  This happens in the first squatter's camp in Chapter 20 and again later, before entering the Hooper farm to pick peaches in Chapter 26.  Later, in that same chapter, Tom has to be hidden because of the incriminating injury to his face.  Ma again expresses the attitude that as long as the family is together, they can face any problem.

Throughout "The Grapes of Wrath," Ma holds the family together. After the men return from selling everything they can, the family

met at the most important place, near the truck.  The house was dead, and the fields were dead; but this truck was the active think, the living principle.

As the men squat near it, the women stand with their hands on their hips behind them.  Steinbeck writes that Grampa "was still the titular head, but he no longer ruled....His position was honorary."  As the men debate about feeding an "extra mouth" in Jim Casy, the preacher, a determined Ma says that they will not turn him away, for no Joad has been that mean:

As far as 'kin,' we can't do nothin', not go to Clifornia or nothin'; but as far as 'will,' why, we'll do what we will.

The group waits for Ma whenever she goes somewhere, "for Ma was powerful in the group." As the family travels down Route 66, Sharon tells her mother that she and Connie, her husband, do not want to work in the fields.  Upset, Ma tells Sharon, "It ain't good for folks to break up."  Then, when the Wilson's vehicle breaks down, Mr. Wilson tells Pa that he and his wife will stay behind.  However, Ma stoutly states,

I ain't a-gonna go....On'y way you gonna get me to go is whup me...All we got is the family unbroke.

This insistence upon keeping the family together, this insistence on the importance of community is what unifies all the workers; it expresses Steinbeck's belief in socialism, the community of man.  Underscoring this concept, Steinbeck has Ma promising the father of the girl that her son Al has been "walking with" each night:  "We'll try an' see that we don't put no shame on you."  And, in the final chapter, Ma urges Rose of Sharon to share her breast milk with a starving man who has sacrificed his food so his son can eat. "I knowed you would!  I knowed!" Ma says to her daughter.

When Tom must run from the police after the sacrificial death of Jim Casy, knowing Ma's insistence upon family and the belief in the community of man, he returns to his mother and tells her,

I'll be around in the dark; I'll be ever'where--wherever you look.  Wherever they's a fight, so hungry people can eat, I'll be there.  Wherever they's a cop, I'll be there....And when our folks eat the stuff they raise an' live in the houses they build--why I'll be there.