Among the crowds on The Mall today there will have been many people claiming that they're the greatest royal fan. But that title must surely belong to Margaret Tyler who has the biggest collection of royal memorabilia in the country - more than 10,000 items.
London Tonight's Business Correspondent Glen Goodman reports:
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In a wide-ranging Peston on Sunday interview, he said Parliament security needs reviewing and the PM's counter-terror strategy is flawed.
The terror attack carried out by Khalid Masood at Westminster that left four people dead lasted less than two minutes say police.
Two knives were found at the scene in Islington, North London, and the suspects fled on foot before being arrested.