Margaret Thatcher insisted on footing the 1,800 bill to find missing son Mark when he got lost in the desert

How Mrs Thatcher personally paid son Mark's bar tab and the 1,800 cost of his rescue operation after he went missing during Paris-Dakar rally | UPDATED: 16:56 GMT, 28 December 2012 After her son Mark got lost in the desert competing in the Paris-Dakar rally, Margaret Thatcher shed a rare tear in public. When it came to paying for his rescue, however, the 'Iron Lady' was firmly back in the driving seat and at pains to ensure she personally, not taxpayers, footed the bill for her hapless off-spring's misadventure. With questions being asked in Parliament about the cost of the operation, she ordered a breakdown of Foreign Office expenses…