Luigi Mangione, accused of killing UnitedHealthcare CEO Brian Thompson, celebrated his 27th birthday in jail with a reflective letter.

Mangione marked his 27th birthday with a list of "27 Things I'm Grateful For" that he sent to various people who have been writing to him in jail and that is now circulating online.

Luigi Mangione is not writing a confession. He’s not asking for forgiveness. And he’s definitely not retreating into silence. Instead, ...