Giving a best man speech is nerve-wracking enough—but when the groom is the future King and your own brother, the pressure is on.

At Prince William and Kate Middleton’s royal wedding in 2011, Prince Harry delivered a best man speech that struck the perfect balance between cheeky humor and heartfelt emotion—one that reportedly left the Princess of Wales wiping away tears.

Royal author Christopher Andersen shares new insights into the speech in his book Brothers and Wives, revealing just how close the two princes once were—and how much Harry clearly adored his new sister-in-law.

According to Andersen, Harry kicked things off with a laugh, jokingly apologizing to Kate “for having to marry a bald man.” He also delighted guests with hilarious impressions of William “cooing down the line at Babykins”—Kate’s affectionate nickname—and mentioned that she called her new husband “Billy.” He affectionately dubbed the couple “the dude and the duchess.”

But it wasn’t all laughs.

“There were muffled sobs when Harry told his brother, ‘Our mother would be so very proud of you,’” Andersen wrote. “And sighs when he said he loved Kate like a sister.”

The emotion in the room was palpable. Kate, touched by the sincerity of Harry’s words, was seen wiping away tears during the speech—especially when Harry admitted that her and William’s long love story had been “an inspiration” to him.

Some edits were made to the speech beforehand—reportedly at the urging of Harry’s then-girlfriend, Chelsy Davy. One cut line? A comment praising Kate’s “killer legs.”

The celebration continued late into the night, with Pippa Middleton transforming the palace’s throne room into a full-blown nightclub. Fireworks lit up the sky, capping off the royal festivities.

As the night drew to a close, an emotional Harry was seen putting his arms around William and Kate, quietly weeping. The bride and her brother-in-law comforted each other, brushing away tears, while William—amused and dry-eyed—looked on.

“People don’t realise how much Harry and Kate love and help each other,” one guest remarked. “It’s key to this whole thing.”

In the years following the wedding, the trio worked closely together on charitable projects, forming what many called “the royal trio.” Though much has changed since then, this touching moment offers a glimpse of the deep bond they once shared.