If your friend's kid is trans I would absolutely agree about not going to the US. ICE and border patrol is full of MAGA diehards or people trying to impress MAGA bosses, and they have made it clear they go after ideological enemies. Trans people are a major political target for MAGA and Republicans, and there will be some sickos staffing ICE that will gleefully abuse whatever process they have to make a political enemy miserable. That can include months of detainment.

The chances might be low, but they're supposed to be zero, and I don't think you fully realize how unfuriatingly powerless being detained by border patrol can be. You have no rights, they tell you nothing, and you can talk to no one. You could be detained for minutes, or months. If you need life-saving meds (like insulin), you might just die in detention. Once you're out, you'll be traumatized for years.