Prince William, also angered by the comment on behalf of his wife, then confronted Meghan according to author Robert Jobson’s book Catherine, The Princess of Wales: The Biography.
According to the book, Meghan was left in tears by the confrontation, though Kate later attempted to smooth things over by sending her flowers to apologise, and Meghan apparently accepted the gesture.
But the tension lingered between the couples, as William and Kate met with the newlywed Harry and Meghan after their honeymoon, with Kate wanting an apology over the “baby brain” comment.
The heir apparent had also called Meghan “rude” for talking about his wife’s hormones after the birth of their son.
The confrontation escalated quickly, with Meghan allegedly snapping back at William with a blunt seven-word retort: “Take your finger out of my face.”
Reports have long suggested Kate and Meghan were never close, with some high-profile disagreements fuelling speculation of a rift.
Most infamously, the two duchesses are believed to have clashed over Princess Charlotte’s bridesmaid dress in the run-up to Harry and Meghan’s Windsor wedding.
Harry initially wrote about the “baby brain” dispute in his bombshell memoir Spare, published in 2023, describing it as one of several moments that soured relations between his wife and his sister-in-law.
The Sussexes stepped back from royal duties in 2020 and have since relocated to California, where they live with their two children, Archie, six, and Lilibet, four.
Meanwhile, William and Kate have continued to step up their public roles as the Prince and Princess of Wales, preparing for their future as King and Queen.