LitCharts assigns a color and icon to each theme in The Sun is Also a Star, which you can use to track the themes throughout the work.
Immigration and the American Dream
Passion vs. Reason
Interconnectedness and Destiny
Isolation vs. Connection
Summary
Analysis
Daniel thinks that he does not want to go to his interview, but it is fast approaching. He thinks about the moment he and Natasha shared and wishes they could talk about it. They finally reach a massive skyscraper. He offers to wait for Natasha outside, and she sternly tells him no. Daniel thinks that this is the voice she'll use to discipline their future children.
When Daniel continues to see his future with Natasha, the novel makes the case that time is connected in the same way people are: they all influence and inform each other, and it's absolutely possible to pick out elements of one's future in the present.
Active
Themes
Daniel wonders if Natasha is a convenient excuse to derail the future his parents set out for him, but reasons that she's right; there's no future for them since she clearly doesn't like him. He agrees to go, and Natasha seems surprised and even disappointed.
The fact that Daniel appears to be looking for an excuse to not go to Yale indicates that he believes he needs a reason other than that he simply doesn't want to.