Princess Diana 'caught up on sleep' during her honeymoon

A batch of letters written by Princess Diana to her personal secretary, Jane Parsons M.B.E., is going to be auctioned off in April. The contents of the correspondence reveal, as the auction house puts it, an "intimate glimpse into the marriage" of Prince Charles and the late Princess.

In the letter that is sure to generate the most interest, dated August 15, 1981, Diana writes from her honeymoon, on Royal Yacht Britannia–crested paper: "The honeymoon was a perfect opportunity to catch up on sleep...." (Expect at least an entire episode of Ryan Murphy's upcoming Charles-and-Diana–focused Feud season to be spent on just this detail alone.)

Other intriguing tidbits gleaned from the letters:

Prince William received 4,500 baby presents on the occasion of his birth (and there were a total of 24,000 thank-you notes sent out after the fact—which should make you feel deeply embarrassed about how much you dread having to write even just a single thank-you e-mail).

See photos of from Princess Diana and Prince Charles' wedding:

— Diana kindly wanted to ensure that her staff was not feeling "exhausted, overworked and underpaid" after William's birth. She herself felt somewhat deluged, explaining to Parsons, after her own 21st birthday, "I have never been more confused than on my birthday as presents and telegrams were pouring in for W at KP as well as my own—so at the moment I just seem to be churning out letters!"

More: Kate Middleton's Best Looks of 2016

— Diana was very happy that William was excited to see her when she returned home from a trip to Australia in 1983. (She also, uh, does not seem to necessarily have loved all the traveling . . . ) She wrote, "William recognised us instantly, which was a relief as sometimes children resent their parents leaving them! It's marvellous to be home again and hopefully we won't have to do any more travelling this year... Wishful thinking!"

— She had a lot of photos of William (O.K., this one isn't so shocking). "Recently I seem to have endless pictures of William, so it's lovely to think I'll be able to frame one of them for our bedroom," she wrote.

See more photos of Princess Diana:

More from Vanity Fair:

Pics of Royals Skiing Through the Years

Remembering Princess Diana's Glamorous Style

13 Photos That Prove William and Kate Are a Perfect Couple

Prince Harry's Best Style Moments