However, Lady Louise may not have been the only royal unaware of their important family role.
The Queen’s grandson, Prince William, and his wife, Kate Middleton, have previously said they try to be as normal as possible with their children.
They are parents of three: Prince George, six, Princess Charlotte, four, and Prince Louis, one.
Speaking to BBC in 2016, Prince William said: “As far as we are concerned, within our family unit, we are a normal family.
“I love my children in the same way any father does, and I hope George loves me the same any son does to his father.