A lot about being a first lady is unofficial. The title is invented, the job unpaid and the mandate unclear: Be fashionable but not flashy; be involved but not interfering. Pick a cause, make a mark — but not too much of a mark.

First lady Melania Trump attended Barbara Bush’s funeral on Saturday in Houston, participating in another of these informal traditions: A delegation of first ladies, both present and past, has attended every funeral of another first lady since the 1960s.

Legend has it that President Zachary Taylor may have coined the term “first lady” at the funeral of Dolley Madison in 1849, according to the National First Ladies’ Library. However, no records of his eulogy exist to prove this claim.

During the presidency of her husband, James Madison, Madison performed the hostessing and philanthropic duties associated with a president’s spouse and may or may not have saved George Washington’s portrait from British torches during the War of 1812. It’s likely that Taylor’s wife, Peggy, and John Quincy Adams’s spouse, Louisa Adams, also attended her funeral. But while Madison’s death garnered attention, it didn’t take on the quasi-state funeral air of later years.

Barbara Bush, who was the wife of one president and the mother of another, died on April 17. (Monica Akhtar/The Washington Post)

(No first lady has ever been given an official state funeral. They’re generally accorded the same courtesies as military family members at Arlington National Cemetery, meaning family can request military body bearers and a military chaplain, according to the Defense Department.)

First lady Julia Grant, wife of Ulysses S. Grant, made a point of bonding with other first ladies in her lifetime — Lucy Hayes, Lucretia Garfield, Frances Cleveland. She even befriended Varina Davis, widow of former Confederate president Jefferson Davis. Still, none are known to have gone to her funeral in 1902. President Theodore Roosevelt, however, did, suggesting “a growing respect for the status of presidential spouse,” according to the National First Ladies’ Library.

Then came the funeral of the longest-serving and, arguably, one of the most powerful first ladies in history, Eleanor Roosevelt. When she died in 1962, President John F. Kennedy ordered all flags flown at half-staff, the first time this honor had been given to a first lady. He also flew to New York for the funeral, along with other world leaders and, notably, a group of first ladies: Jacqueline Kennedy, Bess Truman and future first lady Lady Bird Johnson.

The New York Times described the scene: “First Lady Jacqueline Kennedy twice bit her lower lip and blinked rapidly at particularly moving moments in the religious tributes. Mrs. Truman did not weep within sight of observers, but she hung her head low and took a place of concealment behind the men.”

It’s likely these women attended not because of a feeling of sisterhood, but because of Roosevelt’s particular stature as a national leader. The year before, no first ladies attended the funeral of Edith Wilson, despite her being friendly with several. Still, since Roosevelt, a contingent of first ladies has attended every funeral of another first lady.

In 1979, Pat Nixon joined her husband at the funeral of Mamie Eisenhower. But first lady Rosalynn Carter also attended, solo, despite having only met Eisenhower once. It’s Carter’s apparent gesture of solidarity that seems to have codified the convention, according to the library.

A few years later, Carter attended the funeral of Bess Truman, along with Nancy Reagan and Betty Ford. Nixon’s 1993 first lady funeral delegation fell along party lines (only fellow GOP first ladies Ford and Reagan attended), though probably by accident. Jacqueline Kennedy had requested a small, family-oriented service, but in 1994, Lady Bird Johnson and Hillary Clinton still made the cut.

Five first ladies attended Johnson’s funeral in 2007, and four each went to Ford’s and Reagan’s. (Barbara Bush missed Reagan’s funeral but attended the burial.)

Four first ladies came to Houston on Saturday to honor Bush: Melania Trump, Michelle Obama, daughter-in-law Laura Bush and Hillary Clinton. Carter, 90, is recovering from surgery and was unable to attend.

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