THE DIRECT descendants of a glamorous socialite who proved a society sensation 200 years ago will attend a special ceremony in her honour.

The 14th Duke and Duchess of St Albans will attend the unveiling of a blue plaque in memory of the 9th Duchess Harriot Mellon today. [Friday]

A society beauty, the duchess was a star of the stage and a model for great painters of her age before bagging herself a wealthy banker and then a young duke.

The current duke and duchess will be the star guests alongside deputy mayor Mo Marsh at an unveiling of a new blue plaque to her in Regency Square, Brighton, from 11.45am this morning.

The future duchess was born Harriot Mellon to a lieutenant father and a mother from a travelling band of actors and she followed her mother into the world of theatre making her stage debut at the age of ten.

She was introduced to her MP, playwright Richard Brinsley Sheridan, who eventually invited her down to Drury Lane to perform.

Her performances caught the eye of the wealthy banker, Thomas Coutts of the bank famously favoured by royalty, although he was 42 years her senior.

Following the death of Coutts’ wife in 1815, the pair married and they were happily married for seven years until he died.

Already widely celebrated for her beauty, she was painted by George Romney and Sir Thomas Lawrence, in 1822 she gained another great advantage by inheriting her dead husband’s incredible wealth.

As well as hosting glamorous parties at her London homes, she also spent considerable time at her Brighton house - St Alban's House in King’s Road on the corner of Regency Square.

In 1827 she flipped the age gap in her second marriage to William Beauclerk, the 9th Duke of St Albans, who was 23 years her junior.

She died in 1837 with her property and fortune going to her step-granddaughter on the condition she changed her name to Angela Burdett-Coutts.

Roger Amerena of the Brighton and Hove Commemorative Plaque Panel said: “It is a new plaque to replace an old Brighton Corporation plaque from about 40 years ago which has become very difficult to read.

“The new plaque will retain the old coat of arms of the Brighton Borough.

“The Regency restaurant has kindly paid for the plaque and for a small celebration afterwards.

“This is the second corporation plaque we’ve been able to replace, the first was for engineer John Saxby at Brighton station.

“There will be others that we will replace but the difficulty is finding people willing to pay for them.”

TheBrighton and Hove Commemorative Plaque Panel is encouraging existing property owners to fund replacements of old Brighton Corporation plaques with blue and white ceramic ones.