Princes in the Tower "the murther of his nephews towards the world", indicating that the boys did indeed meet their end during Richard's days. It is also unlikely that the princes would have been kept alive in secret by Richard for 2 years after their last sighting while rumours of his responsibility for their murder circulated. Some writers have also accused John Howard, 1st Duke of Norfolk; Margaret Beaufort, Henry VII's mother; and Jane Shore (Edward IV's mistress). Pollard writes of these theories: "None deserve serious consideration. The problem with all these accusations is that they beg the question of access to the Tower
Princes in the Tower John of Gaunt, 1st Duke of Lancaster through John Beaufort, son of John of Gaunt on his mother's side, Buckingham may have hoped to accede to the throne himself in due course; alternatively, he may have been acting on behalf of a third party. Some, notably Paul Murray Kendall, regard Buckingham as the likeliest suspect: his execution, after he had rebelled against Richard in October 1483, might signify that he and the king had fallen out; Weir takes this as a sign that Richard had murdered the princes without Buckingham's knowledge and Buckingham had been shocked by it. A contemporary