Rev. Dr. Martin Luther King’s eldest daughter Yolanda King died on Tuesday.

The actress and motivational speaker collapsed and died whilst visiting her brother Dexter at his home in Santa Monica, California. She was 51.

Steve Klein, a spokesman for the memorial King Centre in Atlanta, said that relatives suspect she died of a heart problem.

Joe Solmonese President of Human Rights Campaign, America’s largest LGBT rights organisation, said:

“Following in the footsteps of her mother and father, Yolanda King was a passionate advocate for justice and equality for all people.”

“She was a true friend of the GLBT community and was always eager to lend her talents and support to help advance the mission of many different causes for our community.”

“We were honoured to have Ms. King appear at several Human Rights Campaign events throughout the years where she always brought a message of hope and inclusion.”

The King family said in a statement: “She was an actress, author, producer, and advocate for peace and non-violence, who was known and loved for her motivational and inspirational contributions to society.”

President Bush and the First Lady have expressed their sadness at King’s death and offered condolences to her family.

King founded Higher Ground Productions in 1990 and led it for 17 years. The company’s aim is to create “high-quality and highly entertaining projects for theatre, film and television that celebrate our common humanity.”

High Ground Productions said in a statement on their website: “It is with deepest sadness that we say goodbye to our founder and CEO Yolanda Denise King.”

“Through the projects she championed and her thousands of appearances around the world, she brought to life the vision of a united human community and the potential that we all share to be true agents of change.”

“Her energetic spirit will continue to inspire our work as we move forward.”

King had an active political and creative life. She sat on the Board of Directors of the King Centre, served on the Partnership Council of Habitat for Humanity, and was a sponsor of the Women’s International League for Peace and Freedom.

She was also a spokeswoman for the National Stroke Awareness Association and worked for the American Heart Association, following the death of her mother last year.

King held a BA Honours degree in theatre and Afro-American studies from Smith College in Northampton, Massachusetts, as well as a master’s degree in theatre from New York University.

King had a number of television and film appearances. In 1978 she played Rosa Parks in the TV series King , which was based on her father’s life.

A public memorial for Yolanda King will be held on 24th May at Ebenezer Baptist Church Horizons Sanctuary.