Prince William and Kate Middleton briefly split up in 2007 during their dating phase.

William and Harry introduced acts at a 2007 Princess Diana tribute concert on an unearthed tape.

Judi James found William's awkward dad-dancing and Harry's expressionless reaction.

While encouraging Harry to join in, William appears to be conversing with his fiancée, Chelsy.

Kate was seated a few rows back, most likely due to the break-up.

Chelsy was the first to notice William's attention-seeking dance, and she immediately informed Harry of it.

Harry reacted like a teen whose father was humiliating them at a party.

William seemed to be gloating to Kate about his freedom and enjoying life without her, but he wasn't ready for this body language ritual.

Most likely, this was a small swan song before marrying Kate.