The clip shows the foursome speaking at the Royal Foundation Forum charity event, and when William is asked if they ever have a disagreement, the future king of England replied, 'oh yes', before Harry chirps in 'healthy disagreements'.
Many royalists have now re-posted the video as proof of a royal rift.
In the clip, the Duke of Sussex admits that the arguments come 'so thick and fast' that he's not even sure if they've resolved from their last row.
Wiliam then says: "Is it resolved? We don’t know."
Check out the clip below so you can decide: harmless joke or feud proof?