By the end of the 1940s Macmillan’s children were neither happy nor settled. His son, Maurice, was showing all the signs of serious alcoholism. His eldest daughter, Carol, although married to a successful insurance broker, Julian Faber, was reported as having her mother’s “capacity for irritable boredom”. Catherine, the third child, showed all the signs of Macmillan’s depressions until she married Leo Amery’s son Julian in 1950.

The fourth child, Sarah, although Macmillan had been affectionate towards her, was living on the edge of breakdown. She was convinced — not least because she was constantly told so — that she was [Robert] Boothby’s daughter. On one occasion when she was dancing with a clumsy young man who trod on her toes and apologised earnestly in deference to her father’s political status, “she exclaimed with furious misery: ‘You’re dancing with the most famous bastard in England. Everyone knows I’m Bob Boothby’s daughter’.”

By 1952 the big family house at Birch Grove had been restored (it had been let to a boy’s preparatory school in 1945) and brought into domestic action. This signalled an improvement in the Macmillan marriage. For the first time for 12 years Macmillan was able to sleep in what he regarded as his proper home and, although he and Dorothy were still living apart, the relationship was cordial and respectful. Maurice was a shade more restrained in his drinking and Sarah had found an acceptable boyfriend: Andrew Heath. All this made for a more settled home life and Macmillan was looking every bit a confident Tory minister.

In March Macmillan heard that Andrew Heath had been taken ill with pleurisy and a tubercular abscess on his lung. He had been rushed to hospital and operated on. The marriage in late April was cancelled. But there was a further complication: Sarah had become pregnant. She confided in her mother, who insisted that she get an abortion — on the grounds that if she had the illegitimate baby, it would ruin Macmillan’s career. The abortion was duly done, when and where is not known. Tragically, the operation was bungled and Sarah was left unable to have children of her own. Boothby knew about this — presumably because Dorothy told him. It was, he later said, “the one thing I could never quite forgive Dorothy, the one wicked thing she did . . . I think it was all part of her guilty conscience, but it killed [Sarah].” There is no doubt that Dorothy was taking a grave risk. In those days, procuring an abortion was a criminal offence. Even though Sarah may have had the operation abroad, if the business had come out in the press Dorothy would have been seriously embarrassed – as would Macmillan.

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Sarah finally married Andrew Heath in July 1952. She wrote to Macmillan to ask him, as was customary, to give her away. Macmillan wrote back that he was content for her wedding to be at some date between July and September. He added: “You have had a long wait and a very difficult time, which I think you got through with great courage and good sense.” In the light of this exchange, it may be that he knew about her abortion. Although still on a severe diet after a gall-bladder operation, he put up a good front on the day.

Dorothy, too, was a creature of her time and upbringing. But, apart from her sexual waywardness, she became a model wife for the occasionally fractious Prime Minister — jolly, charming, wholly without snobbery, always interested in other human beings of whatever class or race, adored by servants and full of the humour and life, which made Downing Street a joy for her grandchildren. She still made sorties to see Boothby, but these now were more visits of old lovers rather than the flames of a new passion: she had put on weight and Boothby had started to look decadent. Almost in compensation for what had happened in the past, Dorothy had become the spirit of Birch Grove. On high days and holidays she would organise parties for grandchildren, neighbours and neighbours’ children — cricket matches, fireworks, tennis and so on — while Macmillan “sat quietly reading in the summer house”.

If the grandchildren were a source of delight both to Macmillan and Dorothy, their children were less so. All four of them had inherited a propensity to alcoholism. Maurice had courageously struggled to rid himself of it, and by the end of the 1950s seemed to have done so, but his system had over the years suffered great damage. His wife could not get on with her mother-in-law and thought her father-in-law was unfairly blocking Maurice’s career as a Conservative politician. Catherine, the most beautiful and lively of the Macmillan children, had also succumbed to alcoholism — and disappointment at her husband’s snail-like political career. Carol, although for a time almost succumbing to the blight of alcohol, had in her marriage found a life away from politics. Insurance broking — her husband Julian later became chairman of Willis, Faber — was a much safer occupation.

Macmillan could be either witty and charming or, if occasion demanded, brutally and sarcastically rude. With his family, he was on many occasions the latter. He was not one to tolerate weakness. Whether the alcoholism of his children (and Sarah) was the result of what he liked to call the “Cavendish gene” or of inadequate parental affection is a matter of medical debate. What is clear is that Macmillan either deliberately turned a blind eye or maintained that it could be overcome by a show of character strength. There was also the possibility of prayer. Rab Butler recalled being invited by Macmillan to kneel down with him and pray for Maurice’s release from alcoholism.

Sarah died in 1970 at the age of 39. Her marriage had failed, as had rehabilitation from alcoholism in Switzerland. She seems to have fallen over when drunk and hit her head, the resulting haemorrhage in her brain causing instant death. In 1980, Maurice suffered from a collapsed lung and was near death, only to recover, live on as a near invalid and die four years later, shortly after his father’s 90th birthday.

© Charles Williams 2009
Extracted from Harold Macmillan by Charles Williams, to be published by Orion on June 4 at £25. To order it for £22.50, inc p&p, call 0845 2712134 or visit www.timesonline.co.uk/booksfirst

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