Simplify the following text for a Grade 9 native English-speaking person.
Original: Mary Frances Penick ( December 30 , 1931 -- September 19 , 2004 ) , better known as Skeeter Davis , was an American country music singer best known for crossover pop music songs of the early 1960s .
Simplified: Mary Frances Penick ( December 30 , 1931 -- September 19 , 2004 ) better known by her stage name , Skeeter Davis was a American country music singer .