Much ado about nothing, or a royal rumble that would make professional wrestling jealous? Has the future King of England been pre-flexing his reign, or is this just brothers being brothers? Either way, we're taking a stab at the truth behind Prince William and Prince Harry's feud.

Royal expert Katie Nicholl believes that Prince William questioned the speed at which Prince Harry and Meghan Markle got engaged, then married, which took less than two years. Not surprisingly, Harry allegedly didn't take too well to William's remarks.

Nicholl said in the TLC documentary Kate V. Meghan: Princesses At War:

"William was quite concerned that the relationship had moved so quickly. And being close to Harry, you know, probably the only person close enough to say to Harry, 'This seems to be moving quickly. Are you sure?' And I think what was meant as well-intended brotherly advice just riled Harry."

Nicholl added that Harry is hugely protective of Meghan, leading him to take William's questioning of his relationship with the former Suits star personally.

#RoyalFamily #PrinceWilliam #PrinceHarry

Prince William gave relationship advice | 0:17

Hard feelings pre-wedding | 0:58

Prince Harry wants to be his own man | 1:42

Sussex vs. Cambridge | 2:29

Babies dragged into it | 3:10

Supposedly reconciled | 3:43

They grew apart | 4:27

Concerned for Harry | 5:14

Are they actually feuding? | 5:58