For Will's part, he wrote, "Prince of the United Kingdom," in the "occupation" section of the certificate, while Kate wrote, "Princess of the United Kingdom."

On April 23, Prince William and Kate Middleton welcomed the birth of their third baby, Prince Louis, who has received a royal welcome worldwide. And like every other new parent, they signed the birth certificate for their new bundle of joy. While that certainly isn't unique, what is remarkable is the occupations they listed on the document.

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While the photo of little Louis' birth certificate, and the jobs Will and Kate listed, are certainly noteworthy, it also begs the question: What does that "occupation" actually consist of, and how much does the royal duo make?

Previously, Prince William, 35, held a more traditional job, and worked as a helicopter pilot for East Anglian Air Ambulance for over two years before retiring in July, the Telegraph reports, in order to shift focus to his royal duties.

Now, it's safe to say those duties keep Will and Kate pretty busy, and being a royal is actually a lot of hard work.

The role of the Royal Family — which includes William and Kate — is to assist the Queen in carrying out her duties and also to carry out work in areas of public and charitable service, according to the official website of the British Royal Family. Overall, every year, the Royal Family as a whole carries out over 2,000 official engagements (which can include things like state funerals, national festivities or presenting honors); entertains over 70,000 people at dinners, lunches, receptions and garden parties at the royal residences; and receives and answers 100,000 letters.

There are also around 3,000 organizations that list a member of the Royal Family as a patron or president, according to Buckingham Palace. William and Prince Harry also established the Royal Foundation of The Duke and Duchess of Cambridge and Prince Harry, where Kate serves as a patron. The foundation tackles a number of philanthropic projects, ranging from mental health awareness to cyberbullying initiatives to wildlife conservation.

As for money, the royal family is sitting pretty. After the death of his mother, Princess Diana, Prince William reportedly inherited a fortune of $10 million after taxes, Forbes reports, and began receiving an annual dividend of an estimated $450,000 a year at age 25, and the full sum at age 30.

The living expenses of Will and Kate are also financed by the Duchy of Cornwall, a portfolio of properties, established by Edward III in 1337, with the purpose of providing income for him and future Princes of Wales. Currently, that's Prince Charles (Will's father), who receives the annual income of the Duchy of Cornwall, the Royal Household's website states.

While much of that money is used for his public and charitable work, Prince Charles also uses part of that income for his private life, along with the private lives of his wife and two sons, William and Harry. Prince Charles has made millions from the suite of estates, and it was reported that in 2017, The Duchy reported spending $4.9 million to cover the official duties of Harry, William and Kate. The Duchy includes about 205 square miles in 23 counties, and is predominately agricultural.

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