SIMI VALLEY, Calif. - Guests gathered Friday for Nancy Reagan's funeral at the Ronald Reagan Presidential Library in Simi Valley, California. The former first lady, who died March 6 at the age of 94, will be buried next to her late husband, President Ronald Reagan.

About 1,000 relatives, dignitaries and friends attended the memorial. Former President George W. Bush was in attendance, in addition to First lady Michelle Obama and former First ladies Rosalynn Carter, Hillary Clinton and Laura Bush.

Mourners at the funeral heard former Canadian Prime Minister Brian Mulroney read an adoring letter written by Ronald Reagan to his wife on their first Christmas in the White House in 1981. The letter said she filled his entire life with "warmth and love."

Ronald Reagan's Chief of Staff James A. Baker, as well as journalists Diane Sawyer and Tom Brokaw, a close friend of Mrs. Reagan, also spoke.

Nancy Reagan's daughter Patti Davis described to mourners how the former first lady was adamant about reuniting with her husband, who died in 2004. Davis described her parents as "two halves of a circle," recalling a long-ago memory of seeing the two of them sitting on a Southern California beach at sunset in what she called an impenetrable "island for two."

Son Ron Prescott Reagan told the guests there likely would not have been a President Ronald Reagan without Nancy Reagan, saying she had an absolute belief in him, as well as provided guidance and a refuge. He called her a woman who "knew how to love."

Others in attendance included former Reagan administration official Ed Meese, Katie Couric, Larry King, Mike Love of the Beach Boys, television writer and producer Norman Lear and Steve Ford, son of President Gerald Ford.

Also on hand were dear friends actors Tom Selleck and Mr. T., actress Bo Derek and singer Johnny Mathis. Mathis became friends with Nancy Reagan and often visited her home in the Bel Air area of Los Angeles. Mathis says he and the former First lady enjoyed singing together.

The funeral was held outdoors under tents at the hilltop library northwest of Los Angeles.

The ceremony comes after two days of public viewing at the library. In lieu of flowers, Mrs. Reagan had asked that contributions be made to the Ronald Reagan Memorial Fund at www.reaganlibrary.com.