Prince William's fiancée will be following a tradition started by the Queen Mother. After her wedding in 1923, she placed her floral arrangement at the grave in memory of her brother who was killed in 1915.
On the walk down the aisle, Kate and her father will need to bypass the marble slab; it is the only memorial stone in the church that congregations are not allowed to step on.
Her bouquet will then be returned to the Abbey for placement on the tomb, once the official wedding photos have been taken.
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