The royal baby, who has not even been given a name yet, will inherit US$1 billion, according to Wealth-X. The firm made researches on ultra-high net worth individuals.

The amount was based on an estimate of the worth of the royal baby's family. This excluded the Crown Jewels as well as the Royal Collection from the estimate.

Queen Elizabeth II's worth was placed at US$660 million, said Wealth-X. Meanwhile, Princes Charles, William, and Harry were worth US$370 million, US$20 million, and US$16 million, respectively.

The royal baby's financial inheritance remained secure despite of a proposed law that provided for equal primogeniture.

"The royal baby will inherit his family's wealth, just like Queen Elizabeth inherited her dad's estates and Prince William and Harry were given money from their mother upon her passing. But boy is it nice to be this royal baby! With possibly inheriting $1 billion, this will be the most a royal heir has ever received," said Deputy Editor at TheBump, Elena Mauer.