On the surface, things have never been more joyful for the royal family. Kate Middleton
and Prince William, both 35, are eagerly preparing for the arrival of their babiesidentical twin girls, as Life & Style reported — in April. And Prince Harry is happily getting ready to announce his engagement to Suits star Meghan Markle, who’s been looking for a home in London.

But behind palace doors, new drama is erupting — and threatening to tear the royal family apart. A series of scandals involving members of both Kate’s and Meghan’s families have grabbed headlines across England, infuriating Queen Elizabeth II. The 91-year-old monarch is “sick and tired” of dealing with the constant stories about Middleton and Markle relatives, an insider reveals, and she’s decided to take action.

kate middleton and meghan markle getty images

(Photo Credit: Getty Images)

Her first step: putting together a list of relations Kate and Meghan, 36, need to distance themselves from. Second step: putting her grandsons in the middle. “She’s already spoken to Prince William and told him to pass on her thoughts to Kate,” says the insider. Harry, 33, will soon face the same discomfort. “She worries that when she’s gone, the House of Windsor could fall apart” if she doesn’t do something, the insider says.

Kate’s maternal uncle, Gary Goldsmith, already was notorious for reportedly using cocaine back in 2009. And on Oct. 13, he made headlines again when he was arrested on domestic violence charges for allegedly assaulting his wife. The queen was enraged. Now, says the insider, she’s decided to keep him out of future royal events.

The queen has also considered black listing some of Meghan’s family. On Oct. 23, Meghan’s half-sister, Samantha Grant, went on British TV to promote a book she’s writing, The Diary of Princess Pushy’s Sister, and to say that “of course I would go” to the wedding. Australian mag New Idea also recently published a report that Meghan’s father, Thomas, moved to Mexico after filing for bankruptcy in the U.S. last year. “[The queen] is obviously concerned about Meghan’s family,” says a source. Her advisers have even suggested she ban any relative who’s spoken to the press from attending the wedding. She’s weighing that hard line, says the source, but knows Harry would side with Meghan in a dispute.

Elizabeth’s biggest fear is what’s next. “People worry there are more scandals waiting to erupt once Harry and Meghan are married,” says the source. “The queen has been a shining example for 65 years, and she doesn’t want her legacy to go up in smoke.”