Former first lady Nancy Reagan has died at the age of 94, John Heubusch, executive director of the Ronald Reagan Presidential Library and Foundation, has confirmed.

Reagan died Sunday morning at her home in Los Angeles. The cause of death was congestive heart failure, according to a statement from Joanne Drake, a spokeswoman for Mrs. Reagan.

Reagan's step-son, Michael Reagan, posted a message on social media.

Nancy Reagan, who was born in New York City in 1921, will be buried beside her husand, Ronald Wilson Reagan, at the Ronald Reagan Presidential Library in Simi Valley, California. 

She is survived by two children, Patti Davis, 63, and Ronald Reagan Jr., 57.

The former FLOTUS was well-known for her "Just Say No" campaign, which combated drug abuse in the 1980s and for many other causes including the welfare of veterans. She served as the first lady during Ronald Reagan's eight years in the White House from 1981 to 1989.