This episode covers incidents of mass violence.At least 21 people, including 19 children, were killed when a gunman opened fire at the Robb Elementary School in Uvalde, Texas, on Tuesday morning.It was the deadliest school shooting in the United States since the 2012 attack on the Sandy Hook Elementary School in Newtown, Conn.For some of the Sandy Hook parents, news of yet another school massacre provoked a chilling sense of numbness.Guest: Elizabeth Williamson, a feature writer for The New York Times and the author of a book on the aftermath of Sandy Hook.Want more from The Daily? For one big idea on the news each week from our team, subscribe to our newsletter. Background reading: Some Sandy Hook parents whose children were killed in the 2012 attack in Newtown, Conn., shared their emotions and responses to another school shooting.President Biden said that it was “time to turn this pain into action” in remarks following the massacre in Uvalde.For more information on today’s episode, visit nytimes.com/thedaily. Transcripts of each episode will be made available by the next workday.