Simplify the following text for a Grade 6 native English-speaking person.
Original: Nancy Davis Reagan ( born Anne Frances Robbins on July 6 , 1921 ) is the widow of former United States President Ronald Reagan and served as an influential First Lady of the United States from 1981 to 1989 .
Simplified: Nancy Davis Reagan ( born July 6 , 1921 ) is the widow of Ronald Reagan , the President of the United States . She acted as the First Lady of the United States from 1981 to 1989 .