British royal Prince William became $15.7 million richer on his 30th birthday on Thursday (21Jun12) by inheriting the money left to him by his late mother Diana, Princess Of Wales.

The age milestone means the prince is eligible to receive the windfall under the terms of his mother's will, according to Britain's Daily Mirror newspaper.

At the time of her death in a car crash in Paris, France in 1997, Diana's estate was worth $20.3 million after tax deductions of $13.3 million , but shrewd investment means the value has since risen to around $31.4 million .