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
Natasha moves closer to Daniel again, and Daniel wonders if part of falling in love with someone else includes falling in love with yourself. He likes who he is with Natasha. He reads the next question: how does she feel about her relationships with her mother and father. Daniel struggles to articulate how he feels about Dae Hyun. He loves him, but their relationship is fraught. He doesn't know how much is normal teenage stuff and how much has to do with the cultural divide. Natasha teasingly asks if Daniel just feels bad about it, and Daniel thinks it's a concise way to describe a very complicated situation.
Daniel does have the added complication of having been born in the US, while Natasha has more in common with both of her parents simply by virtue of being all first generation immigrants. For Daniel, the American dream is an entirely different beast because he never has to deal with the struggle of actually getting to the US and becoming a citizen—that's something he received freely at birth.
Active
Themes
Daniel explains that he has a good relationship with Min Soo, as they're both artistic. Natasha doesn't want to answer the questions, but agrees to give thumbs up or thumbs down for each parent. She gives Patricia a thumbs up and Samuel a thumbs down.
It's worth considering that by telling Daniel about her parents, Natasha has to actually consider how she relates to her parents. Figuring that out seems to be as much a part of the problem as anything else, which is why she settles for a simple thumbs up or down.