It's Visiting Day, when the parents come to see their kids and hopefully bring snacks. But since Tris kind of, sort of, totally abandoned her family, she's not expecting to see Mom or Dad.
But, surprise, Tris's mom does come; and double-surprise, Tris's mom seems pretty comfortable with the whole Dauntless thing—the tattoos, the Pit, the bandages from broken noses, etc.
And mom seems pretty comfortable with Four, too, whom she describes as "handsome."
Four tells mom that Tris is doing well, which is true, if by "well," he means "getting knives thrown at her."
In case you like Tris's friends and want to know how they're doing, Christina and Will visit with their family, but Al stays in the dorm to hide from his family.
Will's Erudite sister Cara actually starts to argue with Tris's mom. (Remember: Erudite hate Abnegation because Erudite think Abnegation are hoarding goods and not leading the city well. Yay politics.)
Instead of fighting, mom takes Tris to go talk about how things are, and reveals that she herself was born Dauntless—which is why she's so familiar with all the Dauntless ways.
And her mom also seems to know that Tris is Divergent, or at least that she got unclear test results.
So she tells Tris to try to blend in with the ranking—she should aim for the middle of the rankings so people don't suspect that she's special.
Mom's final message is for Tris to find her brother in the Erudite compound. Tris should ask him to research the simulation serum.
This is totally different from how our Visiting Days usually go, but we can roll with it.