Tensions are said to have been simmering between the Yorks and the Sussexes ever since Harry and Meghan got married.
A pal told The Telegraph: “It’s fair to say the relationship is not what it was.”
The pair chose not to invite Sarah, Duchess of York, to their wedding reception, and then reportedly sparked irritation by announcing Meghan’s pregnancy at Princess Eugenie’s reception.
Harry then came alone to the evening bash and only stayed for one drink, with the couple officially announcing the baby news the following day.
Another friend added: “Of course Harry and Meghan will be invited [to Beatrice’s wedding] but it is up to them whether or not they choose to attend.
“The trouble with Harry and Meghan is that they think they are bigger than the institution.
“It’s such a shame things have turned out like this.”
And a source close to Zara last night said: “The overwhelming feeling is just one of sadness.
“She is incredibly fond of Harry and just feels so sad about what has happened. That’s how they all feel.”