As convoluted as the laws of royal succession may be, at least one provision is unquestionably clear: male heirs are favored over females in the line for the British throne.
Blame such discrimination on the Act of Settlement, which dates back to 1701, making it even older than the U.S. Declaration of Independence.
Specifically, the law says that a younger male heir supersedes an older female in the line of succession to the throne.
The upshot is that if Prince William and Kate Middleton have two children, say, a girl and then a boy, their son would become first in line to the throne, not his older sister.
Keith Vaz, a British Labour Party member of Parliament, says the succession law's time has passed and he wants to change it.
The push comes ahead of the April 29 wedding between Prince William and Kate Middleton.
The laws governing the British Royal Family should be modernized, Vaz of Leicester East argues.
His aim is to "remove any distinction between the sexes in determining the succession of the throne."
"The law was outdated in the 21st century," Vaz said. "People expect that discrimination of any kind should not exist and there should be equality regardless of race, gender or religion.
"Some of the United Kingdom's most successful monarchs have been women, no one less than our present Queen, Elizabeth II," the politician said.
"If the current succession laws did not exist, Princess Anne would be fourth in line to the throne rather than 10th, while her daughter, Zara, would be sixth in line rather than 12th."
But Charles Kidd, editor of Debrett's Peerage and Baronetage, raises another issue: religion.
"Female discrimination is just a custom," Kidd said. "The act of settlement is to keep the order of succession Protestant."
"It's a religious act," Kidd added.
As it stands, members of the royal family who marry a Catholic, or someone from outside the Church of England, lose their place in line for the throne.
Whatever the perceived offense, it may not be easy to change the law. It would require the agreement and cooperation of the 15 independent British Commonwealth countries, which also call Queen Elizabeth their sovereign.
Government Recognizes the Problem
The government has acknowledged, however, that it "accepts that the provisions in the Act of Settlement could be discriminatory."
As for now, Prince William is second-in-line to the throne, behind his father, Prince Charles, but the queue behind them might be in for a shuffle.