Prince William and Kate Middleton’s child will be granted the title of “princess” if it is a girl, according to a decree made by Queen Elizabeth.

According to Today News, the Queen has updated a rule established by King George V in 1917 that stated a first born royal daughter could only receive the title of “lady,” and that sons would automatically be titled “prince.”

Queen Elizabeth issued the decree on Dec. 31, and it was published in the London Gazette, according to the Detroit Free Press.

Using the "letters patent" process allowed the Queen to establish the update without involving Parliament.

“The Queen has been pleased by Letters Patent under the Great Seal of the Realm dated 31 December 2012 to declare that all the children of the eldest son of the Prince of Wales should have and enjoy the style, title and attribute of Royal Highness with the titular dignity of Prince or Princess prefixed to their Christian names or with such other titles of honor," the London Gazette wrote.

The decree is among many changes that are being made to outdated rules related to royal hierarchy, according to Today News.

In anticipation of Kate’s pregnancy, which was announced in December, the decree also automatically places the royal baby in the line of succession. The child, regardless of gender, will be third in line to the British throne. Previously, only sons could be eligible for the crown.

Today News noted that Queen Elizabeth II was only granted her title because she has no brothers.

Prince William and Kate Middleton’s first born is due in the summer.