When Prince Harry introduced Meghan Markle to Queen Elizabeth II over tea and scones at Buckingham Palace in October, the woman he loves and his grandmother “hit it off immediately,” a source tells Life & Style. Now the monarch “has officially given Harry and Meghan her blessing to be married.”

But their path to the altar is full of obstacles. Planning for the duo’s wedding is officially underway, Life & Style has learned. But new sources of drama keep cropping up, from the couple’s lack of control over the festivities to Meghan’s relatives’ loose lips. “There are lots of unanswered questions about where and when the wedding will take place, how big it will be and who will be invited,” Duncan Larcombe, author of Prince Harry: The Inside Story, exclusively tells Life & Style. “It’s going to be a dramatic lead-up to a unique and mind-blowing wedding.”

prince harry & meghan markle getty images

(Photo Credit: Getty Images)

As an American and a divorcée, Meghan, 36, had to convince the queen she was worthy of her 33-year-old grandson. She did — but now her family is causing problems. On Oct. 23, Meghan’s half-sister, Samantha Grant, went on TV to promote her upcoming book, The Diary of Princess Pushy’s Sister. “There’s so much the public doesn’t know,” the 52-year-old teased of her sibling, who she’s called “selfish” and a “social climber” in the past. “The queen is nervous,” notes the source, who says nothing upsets Elizabeth, 91, more than the wrong kind of publicity. “She likes things to go her way and will be furious if anyone steps out of line at the wedding.” But supportive Harry is letting his bride decide whether to invite Samantha, who has said she “would go” to the wedding. Also on the potential guest list: her half-brother, Thomas Markle Jr., 50, who was arrested in January after drunkenly threatening his girlfriend with a gun. “I still want to go to the wedding if they’ll let me,” says Thomas.

The guest list is one of the few parts of the wedding Meghan has control over. The duo had hoped to wed around Christmas but was forced to push the date back so it wouldn’t interfere with the April arrival of Kate Middleton’s babies. (As we already reported, Kate’s having twin girls!) “Meghan wants to hire her own wedding planner rather than let the palace take charge so that her day can be as personal as possible,” says the source. “But she obviously has to let the royals have their say.”

Her groom is no ordinary royal, though. Known for breaking the rules, Harry is “pushing for a wedding that’s more low-key than William and Kate’s,” says the source, “and that will take place in the countryside just outside of London.” And he’ll get his way, believes Larcombe. “Courtiers and the queen’s advisers may try to influence Harry,” he notes, “but he is very strong-willed and will do what he thinks is best for him and Meghan — not necessarily for the monarchy.

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