“By law Andrew could tell no-one until he had officially asked permission of the Queen and obtained her consent to marry – and the Queen and the Duke of Edinburgh were not due back from their tour of Australia and New Zealand for another three weeks,” Ingrid wrote in her book Sarah: HRH The Duchess of York.
“Just before midnight Andrew went down on both knees and asked Sarah Ferguson to be his wife.
“Sarah was caught off-guard and, to cover her confusion, tried to make light of it.
“She told the prince: ‘If you wake up tomorrow morning, you can tell me it’s all a huge joke’.”
The pair went on to wed in a lavish ceremony in 1986 and divorced a decade later in 1996.
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