The event is held the day before Remembrance Sunday to pay tribute to those who have lost their lives in war.
The Duchess of Sussex and the Duchess of Cambridge were snapped sporting similar looks for the event - black dresses with a red poppy pin.
Rumours were rife of a rift between Harry and William for months with Harry somewhat confirming it with his comment on the ITV documentary that they were on “different paths” and have “good days” and “bad days”.
Royal commentator, Angela Mollard, claims she knows what is behind the brothers' feud, which centres around Meghan Markle.
Speaking on New Idea’s ROYALS podcast, Ms Mollard claimed: “I have a theory on what’s happened there and I don’t think William is at fault.
“So I think it’s pretty obvious what happened, William who spent a long time deciding that he was going to marry Kate because he knew how important it is to this institution and to his concept of duty.
“Which possibly he upholds as the second most dutiful member of the Royal Family on paper, after the Queen I think. he wants a clean copy book to go into the role that he will eventually inherit.
“But I think what’s really interesting is probably what he did say to Harry was something along the lines of ‘are you sure?’
“Which is a reasonable thing to say when you’ve met someone, you’ve fallen in love, she’s American, there’s lots of issues, there’s lots of pressures on them, she doesn’t have the ballast of a close-knit family in the UK.
“It was not unreasonable for William to say to Harry, ‘have you thought about this?’, ‘should we wait longer?’, whatever he said, we know he said something we just don’t know what it was."
“Clearly what’s happened is Harry, in the same way that he is quite reactive with the press and quite reactive in certain situations, was probably very reactive to William.
“Doubtless went home, said to Meghan ‘you won’t believe what William said to me’. Instead of seeing it as a well meaning and caring enquiry, they’ve both obviously got their backs up and now there’s this friction between them.”
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