Harry devotes an entire chapter of Spare to an evening he and Meghan spent at Clarence House with the King while they were planning their wedding. “He wholly endorsed our desire to have an orchestra rather than an organist, and he played an assortment of orchestras to get us in the mood.”

Meghan and the King bonded over their shared love of music (Beethoven for him, Chopin for her) during this planning session, Harry said. “As one piece ended, he’d quickly reload his wireless, begin humming or tapping his foot to the next. He was airy, witty, charming, and I kept shaking my head in amazement.” Harry writes that he knew his father loved music, but until this moment, he didn’t know “he loved it this much.” Harry credited Meghan for this. “[She] evoked so much in him, qualities I’d rarely seen. In her presence Pa became boyish. I saw it, saw the bond between them growing stronger, and I felt strengthened in my own bond with him.”

The Queen gave Harry permission to keep his beard for his wedding (to the annoyance of William, who threatened to hold Harry down and shave him if he got too drunk at his stag/bachelor party):

“After all the stress of asking Granny for permission to marry Meg, I thought I’d never have the courage to ask her for anything else,” Harry writes in Spare. “And yet I now dared to make another ask: Granny, please, may I, for my wedding, keep my beard? Not a small ask either. A beard was thought by some to be a clear violation of protocol and long-standing norms, especially since I was getting married in my Army uniform.” Harry said that Meghan had never seen him without a beard, and wearing a beard helped him with his anxiety. When he explained this to the Queen, she said that she understood, adding that “her own husband liked to rock a bit of scruff now and then.” 

Harry said that this frustrated his brother, who was reportedly told to shave his own beard when he grew one while on an assignment with Special Forces. William was angry that Harry went to the Queen for permission and, Harry writes, “at one point, [William] actually ordered me, as the Heir speaking to the Spare, to shave.” (Harry writes that the beard frustration was in part caused because he was being allowed to wear the military uniform that William wanted to wear when he married Kate.)

At his stag/bachelor party, Harry said, he was afraid that if he “got too drunk and passed out, Willy and his mates would hold me down and shave me.” As it turns out, that was a valid fear. “Willy told me, explicitly, in all seriousness, that this was his plan.”

Meghan was originally going to wear the Spencer Tiara (as famously worn by Princess Diana) for her wedding, but then the Queen offered to loan her one from the royal collection:

Source: https://www.buzzfeed.com/ellievhall/45-details-prince-harry-spare