The retirement as regular weekly show personality will come "this spring" after proper farewell shows, in Chicago or Kasell's home of Washington, D.C., or both, said show host Peter Sagal.

"We want him to be celebrated every place we go for the next few months," Sagal said. "Carl is the popular person on our show. He is the heart and star of it …. He is probably the single most beloved person on NPR. He was everybody's favorite grandfather, uncle, or, going back some, brother by another name."