In this Jan. 17, 2017 file photo CEO of Credit Suisse Tidjane Thiam gestures as he speaks during a panel at the 'World ...

We always knew Fionnuala Jay's wedding look was going to be a knockout and when the first snaps from her wedding emerged we were right.

Princess Diana's backup wedding dress had some similarities to the iconic 1981 original. What were the unique aspects of both gowns?