Anticipating further attacks on the family, the close source claims that the Queen is considering a pre-emptive legal action to protect the royal family from further airing of dirty laundry.
The royal source told The Sun: "The royals' legal team are speaking to firms with expertise in libel and privacy.
"If someone were named in the book and accused of something directly that could be a libel and also infringe their rights to a private family life.
"The legal team could also contact publishers of the book to ask for advance warning of its contents and a right to reply.
"There are concerns that the American public are falling for what Harry and Meghan say."
Since Harry, 36, and Meghan, 40, spilled shock family secrets to Oprah Winfrey in a bombshell interview earlier in the year, it would be safe to assume that the promised memoir will be just as explosive.
Time will tell if the Queen is able to put a stop to the release of Harry's book, or, at the very least, get ahead of the impending scandal and manage to control the narrative.