Although until now British law stated that only firstborn boys are allowed to inherit the throne, Prince William and Kate Middleton’s child, whether a boy or a girl, will become the British monarch when the Queen overturns this law.

The laws of succession over the last 300 years stating that only firstborn boys can inherit the throne will be replaced, as the Queen gives her Royal Assent to the Bill that will end the tradition of men taking over women in line to the throne, Sky News reported.

According to a Cabinet Office spokesperson, the Succession to the Crown Bill has received its third reading in the House of Lords, and will be sent to the 87-year-old monarch “in the coming days or weeks," read the statement.

The Bill will also lift the bar on anyone in the line of succession marrying a Roman Catholic and end the provision that requires any descendant of George II to seek the Sovereign’s permission to marry.

Instead, Sky News reported, only the first six people in line to the Throne will be required to do so.

Since the Bill was announced in Australia, at the Commonwealth Heads of Government meeting in October 2011, the new rules ending archaic Primogeniture apply to any baby born in the line of succession.

Meanwhile, the Duchess' baby bump is growing visibly bigger as her due date nears. The new addition to the royal family is expected to be born in July.