ONE sister was the most photographed woman in the world.
The other will do almost anything to avoid having her picture taken.
While Princess Diana remains a public icon, the years have not been kind to her eldest sister, Lady Sarah McCorquodale.
At 48, she is a bitterly disappointed woman who is notoriously difficult company and prone to outbursts of temper which have made her a number of enemies.
She is painfully thin and her freckled face betrays the signs of years of heavy smoking. And as a mother of three and wife of a Lincolnshire farmer, her life has fallen far short of her early expectations.
For at 23 it was Sarah and not the 17-year-old Diana who seemed set to marry Prince Charles. It was she he courted and she - in an act she regrets to this day - who by her own admission 'blew it' with one foolish moment of indiscretion.
Sarah's decision to become a trustee of the memorial fund set up after Diana's death in 1997 was, in part, an attempt to find a role for herself in an otherwise less than fulfilling life. But it has brought her to the brink of financial ruin because of a [pounds sterling]16million US law suit brought by the Franklin Mint which makes Diana memorabilia.
She and her husband Neil stand to lose their 1,000-acre farm, a Chelsea flat bequeathed to Sarah by her father Earl Spencer, and their stake in an equestrian centre.
Bankruptcy would be the final straw for a woman whose jealously guarded privacy, we can now reveal, masks a deep unhappiness.
A close friend said: 'The fund gave Sarah a purpose other than being a wife and mother. As awful as it may sound, Diana's death gave her something to do and she thought she could do it while remaining out of the limelight.' Yet this week, the glare of the spotlight she so loathes will be focused mercilessly on her as she and her fellow trustees hold a series of crisis meetings.
A friend of the Spencer family said: 'There's a great air of disappointment-about Sarah. It's as if she's had the stuffing knocked out of her. She used to be sparky and witty - really quite dazzling and a bit wild.
All the Spencer girls - Sarah, Jane and Diana - were great fun. Now she's obsessed with control, with living her life within rigid guidelines.'
Expelled from West Heath School, near Sevenoaks, Kent, for drinking vodka, she now touches nothing stronger than cola.
'I'm a whirlwind kind of lady,' Sarah boasted on her engagement in 1979 after a five-week courtship.
Yet friends have suggested she married on the rebound from her relationship with Charles which began at an Ascot meeting in 1977.
She had just emerged from an 'intense love affair' with Gerald Grosvenor, now Duke of Westminster and reputedly the richest man in England, and had been thrown into depression and anorexia.
Her weight plummeted to less than six stone. But within weeks of meeting Charles she had checked into an eating disorder clinic where she was treated by the psychiatrist who would later try to help Diana.
Sarah's relationship with Charles ended after she gave an interview to a newspaper.
A friend says: 'She's never forgiven herself for that. To this day when the Prince comes up in conversation she chips in with, "Of course he was my boyfriend first." On the day Diana was married she said to her, "This could all have been happening to me. I thought all this would be mine one day".'
What 'whirlwind' there may have been in her attraction to the handsome but pedestrian McCorquodale, now 51, seems to have dissipated in the daily grind of life as the farm secretary of his estate.
A former friend said: 'In many ways her life is starting to echo her mother Frances Shand-Kydd's in the latter years of her marriage to Johnnie Spencer.
She got tired of country life at Althorp and spent more and more time in London.' Sarah seems to make the long drive from Lincolnshire with increasing frequency. Friends have noticed that the appeal of country pursuits seems to have dwindled. One source said: 'I'm sure Sarah is very fond of Neil but she regards him more as the father of her children - whom she loves unreservedly - than her partner. They've been married for 20 years which is something to be proud of but they lead pretty separate lives.
'The children - Emily, 19, George, 18, and Celia, 14 - have all come to the fund's offices but Neil never has.
Nor has he ever been at any fund events even when his wife was coming under a lot of criticism and one might have thought she'd want him there for moral support. Until recently she had taken to going on fishing holidays without Neil.
'Her life, especially since Diana's death, has become centred on her flat and her London associates whom Neil doesn't know. She frequently talks about her children and at the moment she is terribly worried about their eldest, Emily, who has just been diagnosed with a rare form [of cancer.] According to one friend: 'She is a very different person from the girl with a wild streak I once knew.
Then she was fun to be with. Now she can be autocratic and cold and, in common with the rest of the Spencers who are never happier than when they're screaming at each other, she has a vile temper.
'Sarah's terribly competitive.
Much as she adored Diana, theirs was a real love-hate relationship which even at its closest was never far from turning sour. I don't think Sarah ever really forgave her sister for "winning".' Another friend recalled: 'When Diana appointed Sarah as her ladyinwaiting in 1992 it was very difficult for Sarah to accept.
'On one hand she was happy to take the handouts and cast-off clothes but on the other it was degrading. Diana did tend to rub her nose in it by lording it over her. The truth is Sarah was insanely jealous of Diana and bitterly disappointed by her own lot in life.' Now, as the Diana trust gears up to fight off the US lawsuit, Sarah seems destined at last to enjoy a taste of her sister's fame.