Tamerlan "swaggered" through the family home like a "man-of-the-house type, " one visitor recalls, while Dzhokhar seemed "very respectful and very obedient" to his mother.

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"They were educated in a system that knew nothing of collegiality and were trained to be obedient to the Pope but in a very, very short time - perhaps two or three weeks - with daring, but gently, they threw out the preparatory materials, " he told Robert Mickens of The Tablet.

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