The upcoming princess, the Royal Family Member,
Kate's sister 27-year-old Pippa, who is to be the maid of respect Friday, is in fits of hysterics, reported.
The 29-year-old has confessed to imagining herself in the buff as the world watches her tie the knot with William.
Kate had suffered a similar anxiety-related dream in 2006 when she was concerning to start a new job at a outfits chain.
"Kate has the last-minute jitters and immediately wants the day to arrive. It's hardly surprising considering the stage she is going to be on - with the eyes of the world on her," a royal source was quoted as saying.
"Other than her nerves have manifested in an interesting way. A returning dream she hadn't had for years has raised its head once more."
In her nightmare, Kate finds herself nude in front of the people attending worship and then becomes unexpectedly aware she is stark naked.
The foundation said: "There is a deadly stillness - and everybody from the Queen to Prince Philip is staring at her... Kate has joked the worst bit is she can't employment out which parts to coat."