Justin gives Olivia a heart necklace for Valentine's day, and she gives him a bag made out of floppy discs. They make plans for Justin to meet Mom and Dad, so they all go out to a Mexican restaurant. Justin's nerves bring out his tics, which used to be bad but now come out only when he's nervous. Via's parents put Justin at ease immediately. He notices that their waiter is shocked by August, but he pretends not to notice. Justin knows that Via noticed. When Via's parents ask Justin about his music, he thinks that he's not used to this kind of attention. His parents never ask him about his life.
When Justin mentions having tics, it implies that he lives with Tourette's Syndrome. This begins to add layers to the way that the novel looks at internal identity (like August's face). In Justin's case, those tics are just as much a part of him as August's face is a part of August, which shows that some of those extremely important identity markers that affect how people move through the world aren't always visible.
After dinner, they go back to Via's house for ice cream. Daisy greets them at the door, and Mom and Dad discover that she threw up. Mom cleans it up while Dad tells the story of how he adopted Daisy. He picks Daisy up, holds her like a baby, and says that a homeless man asked if he wanted to buy his dog. Dad paid the man $20 and took Daisy home, not thinking to ask Mom about it. Justin thinks that Daisy knows how lucky she is to have this family. He thinks of his own family—his parents got divorced when he was four, and they've been pushing him to be independent for a long time. Justin can't remember the last time a family member expressed affection. When he gets home, he finds that his tics have stopped.
When the love and affection that Justin observes between Mom and Dad seems to be the direct cause of his stopped tics, it suggests several things: first, that even older kids still need some parental guidance, and second, that a stable and loving home environment can lessen the impact of differences that could, in the hands of less involved or less caring parents, make life very difficult for the child involved. Daisy's vomiting will be important later, but it's important to notice now that none of the kids seem to take much notice.