Kirk Semple The New York Times

Cristian is one of the tens of thousands of unaccompanied minors who have illegally crossed the border with Mexico in recent months, in a wave that has overwhelmed immigration officials and prompted the Obama administration to declare a humanitarian crisis and open three emergency shelters.

More than 40 years after arriving in New York from Mexico uneducated and broke, Felix Sanchez de la Vega Guzman still can barely speak English. Ask him a question, and he will respond with a few halting phrases and an apologetic smile before shifting back to the comfort of Spanish.

For a few hours over the weekend, a stretch of Madison Avenue in the Flatiron district became an unlikely cash-free zone, a vortex of munificence. And at its center was Kulvinder Singh, a beacon of generosity in his bright yellow turban, who was practically begging passers-by to take free food off his hands."Take!" he implored in a dense Punjabi ac...

Cristian is one of the tens of thousands of unaccompanied minors who have illegally crossed the border with Mexico in recent months, in a wave that has overwhelmed immigration officials and prompted the Obama administration to declare a humanitarian crisis and open three emergency shelters.

More than 40 years after arriving in New York from Mexico uneducated and broke, Felix Sanchez de la Vega Guzman still can barely speak English. Ask him a question, and he will respond with a few halting phrases and an apologetic smile before shifting back to the comfort of Spanish.

For a few hours over the weekend, a stretch of Madison Avenue in the Flatiron district became an unlikely cash-free zone, a vortex of munificence. And at its center was Kulvinder Singh, a beacon of generosity in his bright yellow turban, who was practically begging passers-by to take free food off his hands."Take!" he implored in a dense Punjabi ac...