We know the venue, most of the guest list and even some of the dishes on the menu. But there are some secrets in this royal wedding so big that they have yet to leak to the media. No, we aren’t talking about Kate’s dress; we are referring to their vows, the actual centerpiece of this spectacular event.

The happy couple has reportedly decided on the content of their vows, but royal aides are remaining tight-lipped and not giving anything away.

Will Kate follow in Diana’s footsteps and omit the word “obey”? Or will this modern bride-to-be take a more traditional route and follow in the footsteps of William’s grandmother, Sarah Ferguson and more recently Sophie Rhys-Jones, who married Prince Edward in 1999, and include the controversial word?

Here’s one possible clue: The couple will be married by Archbishop Rowan Williams, who backed a 2006 report by the Archbishops Council, “Responding to Domestic Abuse,” which stated that a “promise to obey was in the past part of different standards and expectations of women and men within marriage, e.g. the fact that women had no standing in law until 1926.”

Kate and William have certainly eschewed tradition in many ways thus far. They have lived together in a cottage near William’s RAF base in Wales, she will arrive at the wedding by car instead of a carriage and it has even been reported that she may prefer to wear flowers in her hair instead of a tiara on the big day, according to the Daily Mail newspaper.

Whichever way they choose, it will be one of the few times the public gets to hear Kate’s actual voice. And if her popularity as a princess-to-be is any guide, it’s not important what she says, but how she says it.