William, a son of Washington Post publisher Katharine Graham has killed himself.

William Graham, 69, died at his home in Los Angeles, according to a Washington Post obituary, which quoted his brother Donald as saying the cause was a self-inflicted gunshot wound.

Graham’s suicide came two days before the Washington, DC, premiere of “The Post,” which recounts the paper’s 1971 efforts to publish the infamous Department of Defense study that revealed massive government lies about American military involvement in Vietnam.

The Steven Spielberg-directed movie features Meryl Streep, as Katharine Graham, and Tom Hanks, as her celebrated executive editor, Ben Bradlee.

William’s father, Philip Graham, committed suicide at age 48 by shooting himself with a 28-gauge shotgun in 1963, days after being released from a psychiatric hospital following six weeks of treatment.

William Graham worked as a lawyer and law professor before founding an investment firm that he dissolved in 2001.

He is survived by his wife, Sally Lasker Graham; two children from the second of his four marriages, Alice Graham and Edward Graham; his sister, Washington Post senior associate editor Lally Weymouth: and brothers Donald and Stephen Graham.