The other figure that's gone missing is of Sir John Houblon, the first governor of the Bank of England. He was the grandson of a Huguenot refugee.
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The twins cubs, which were born in June, have been named Bert and Ernie after characters from Sesame Street.
The two victims died from their injuries in hospital after the explosion in Hertfordshire.
Investigations are continuing into the cause of the crash in chigwell which killed both people on board.