In her 2011 book The Making of a Royal Romance, royal biographer Katie Nicholl said after Kate declined to attend Sandrigham Wills was then asked to join the Middletons on Boxing Day.
The author described how William had promised to join his future in-laws to celebrate Hogmanay at Jordanstone House, but then cancelled at the very last minute, which upset Kate.
“At the last minute William had a change of heart and decided to stay with his own family instead,” Katie wrote.
The author went on to say that Wills told Kate, who was crying at the time, during a late-night conversation on Boxing Day of the change of plan.”
She continued: “For William it was no big deal, but for Kate the cancellation was a sign of something more sinister to come.
“William had been having second thoughts and sat down with his father and his grandmother to have a frank discussion about his future with Kate.
At the time of the reported incident, there was whispers about Wills and Kate getting engaged, but by March 2007 the pair had separated – however, it was short lived as they reunited in June.
Despite getting back together, it wasn’t until November 2010 that Wills and Kate officially announced their engagement.