River Cafe ‘diamond girl’ Daisy Boyd is found dead aged 28

At a glittering engagement party exactly a year ago, Dan Macmillan, heir to a £300 million publishing fortune, and his new fiancee Daisy Boyd were every inch the golden couple.

The sculptress – dressed in a striking black and gold suit – had seemingly tamed wild man designer Macmillan, once dubbed the Vulgar Viscount, the great-grandson of Tory PM Harold Macmillan.

The stylish party at the River Cafe – where her stepfather Charles Pullan, married to her mother Lucy, is manager – left guests anticipating an equally glamorous wedding.

Daisy Boyd and Dan Macmillan attend their engagement party at River Cafe on October 9, 2016 in London

But now her family are devastated after Daisy was found dead, having apparently taken her own life just months after Dan ended the engagement.

The grand-daughter of the late River Café co-owner Rose Gray and daughter of leading architect Tim Boyd was found dead at the private Nightingale Hospital in Marylebone, central London on Thursday.

The circumstances of her death were unclear last night. The hospital, which specialises in the treatment of eating disorders, addiction and other psychiatric illness was judged to ‘require improvement’ on patient safety in the most recent report by the Care Quality Commission (CQC).

Daisy, 28, and 42-year-old Dan, were together for three years before Macmillan broke off the engagement in July.

A family friend said last night: ‘Daisy died on Thursday morning and all her family and friends are devastated by this tragic news. She was just 28 years old and we are all deeply pained that she has died so young. Daisy was a brilliantly vibrant and joyous person who lit up any room she entered.

‘She had an infectious enthusiasm and has been cut off in the prime of her life. Enormously popular, curious, generous and with a diamond sparkle, she was greatly loved by her family and friends, and the gap she leaves is, at the moment, unfathomable.’

The friend said the family wished to grieve in peace.

Daisy was a former pupil of £36,000-a-year Woldingham, a Roman Catholic boarding school in Surrey.

In the past Old Etonian Dan has been romantically linked to models Kate Moss and Jade Jagger, who ended their friendship after finding he was dating them simultaneously.

Daisy's grandmother Rose Gray, left, and River Cafe co-owner Ruth Rogers, right at the venue

Daisy’s grandmother Rose Gray, left, and River Cafe co-owner Ruth Rogers, right at the venue

Heir to the Macmillan family’s £300 million fortune, Dan was also formerly engaged to Ukrainian model Sasha Volkova, but split from her in late 2011. Formally, he is Viscount Macmillan of Ovenden, a courtesy title as he is heir to the Earldom of Stockton.

His father, Tory peer Alexander, the 2nd Earl, sold the Macmillan publishing house to a German firm in the 1990s.

The Macmillans are a troubled dynasty, summed up by some as ‘The Curse of the Macmillans’. Dan’s father, Alexander, watched his own father drink himself into an early grave and his younger brother Joshua die from an overdose in 1965. His sister Rachael died from an overdose in 1987.

Prime Minister Harold’s wife Lady Dorothy had an affair with her husband’s best friend, Lord Boothby, which resulted in an illegitimate daughter, later adopted by Macmillan. This daughter, Sarah, became an alcoholic and died after falling downstairs in 1970.

In June, the CQC found Nightingale Hospital needed to improve patient safety, noting: ‘Staff did not always know the whereabouts of patients […] even when they were potentially at risk of harming themselves or others.’

A spokesman for the £5,000- a-week clinic said: ‘Nightingale Hospital sends our deepest sympathies to the family, but we are not in a position to comment owing to the delicacy of the situation and out of respect to the family.’

Lord Macmillan could not be contacted last night.

For confidential support on suicide matters, call the Samaritans on 08457 90 90 90 or visit samaritans.org.

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