The Woman Who Coined The Phrase 'The Heir And The Spare'

It's an ancient phenomenon. A bunch of royals or aristocrats need an heir to their family title, but they're worried their eldest might keel over and die at some point. They plan to have a backup kid just in case. Maybe he feels a bit overshadowed and acts out accordingly — a sort of youngest-child syndrome on steroids. No matter, he is "the spare."

While the phenomenon is ancient, the saying "the heir and the spare" is quite recent, first coined in the 19th century (via Henry & Poole Co). Most recently, the phrase has been widely discussed in the press due to Prince Harry's new autobiography, entitled "The Spare." Lots of people recognize the prince as the archetypal example of this phenomenon — although according to The Independent, his mother, Princess Diana, never wanted him to feel this way.

Despite its frequent use in discussions of the European aristocracy, according to some accounts, the phrase was actually coined by an American: Consuelo Vanderbilt Balsan. Consuelo married into one of the poshest families imaginable in the U.K. — and quickly got wise to how the aristocracy operates (via Henry Poole & Co).

Americans will be familiar with the railroad-owning Vanderbilts, one of the major celebrity families of the so-called Gilded Age, a time of rapid economic expansion that saw a handful of American businessmen get mega-rich (via Forbes). Brits will be more familiar with the family Consuelo Vanderbilt Balsan married into — the Spencer-Churchills. Long-time dukes and duchesses of Marlborough (via Christie's), this family has since produced the likes of Princess Diana and Winston Churchill.

A famous beauty with a staggering net worth that would be around $4 billion dollars today, the young Consuelo Vanderbilt became a famous socialite in the late 19th century. Yet despite her great good fortune, the Duchess wasn't free to do as she pleased. Although Consuelo was already engaged to marry a man she loved, her own mother, Alva, demanded that she marry into the European aristocracy, setting her daughter up with Duke Charles Spencer-Churchill.

Consuelo did as she was bid and was flung into her new life as a member of the English aristocracy. Perhaps predictably, the marriage was a total disaster, and the pair never grew to love each other.

The pair soon settled into married life at the grand Blenheim Palace, and Consuelo Vanderbilt Balsan performed her wifely duty of pushing out heirs — giving birth to two children. Duke Charles Spencer-Churchill, meanwhile, was busy spending her dowry on refurbishing his palace library (via Henry & Poole Co). It is during their time together that Consuelo is supposed to have (rather coldly) referred to her own children as the "heir and the spare," but her quip was a truth — a frank reflection of the harsh and restrictive nature of the pair's aristocratic marriage. Charles is rumored to have been very cold toward his new duchess (via Christie's), reducing her to the status of a financial bandaid and a broodmare.

Outside of her terrible marriage, Consuelo appears to have had a fairly interesting life. Although some people have unfairly referred to her as a 19th-century Paris Hilton, she was anything but — she was an active supporter of many good causes, including women's suffrage (via NPR) and much loved by the British public. Thankfully, Consuelo later got her happy ending. After divorcing her husband, she married for love, getting hitched to dashing pilot Jacques Balsan in 1921 (via Southampton History Museum).