Some people mentioned that Princess Diana actually bought the heart-shaped necklace herself on the occasion of her son's birth. I am not sure which version is correct. This or the one in which Prince Charles himself gave her this gift.
Also, in addition to the "W" pendant for the bracelet, Prince Charles gave Princess Diana a gold necklace with the round gold pendant with "William" being written in his own handwriting on one side of it as a present for the birth of Prince William.
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