The timing of Prince Harry and Meghan Markle's decision to leave the royal family has reportedly angered Prince William.
The statement by the Duke and Duchess of Sussex revealing their plans to step back as senior members of the royal family was released on the eve of Kate's 38th birthday.
Sister-in-law to Harry and wife of future king William, Kate has reportedly long had a sour relationship with Markle, who married into the family in 2018. At the centre of their feud appears to be their difference in views over upholding royal tradition. While Kate toes the line, Markle has frequently broken royal protocol.
There is also drama between Harry and William, with Harry admitting last year the brothers had recently drifted apart.
The announcement on Thursday looks to have deepened those divisions, with sources telling magazine Us Weekly, that the statement didn't go down well.
"Harry and Meghan rubbed salt into the wounds by making the huge announcement a day before Kate's birthday," a source said.
"It hasn't gone down well with William."
The official Kensington Royal Instagram account posted a picture of Kate on Friday, sending well wishes for her birthday.
Commenting on that picture, Prince Harry and Meghan's account, Sussex Royal, said: "Wishing a very happy birthday to The Duchess of Cambridge today!"
That wasn't warmly received by the public.
"Meghan.... give up ur title and disappear!" said one person.
"Leave her alone" said another.
"Really?????? We've ruined your birthday but happy birthday anyway. Fecken clueless [sic]," added a user.
"You could learn some class and integrity from the Duchess of Cambridge."
It has been reported the Queen told Prince Harry not to publicly announce his plans, but he decided to ignore her. Harry allegedly only gave William and his father, Charles a copy of the statement 10 minutes before it was released.