They’ve ticked off the relationship milestones at lightening quick pace. From a very public confirmation of their romance to spending weeks playing house, and meeting members of the royal family, Prince Harry and Meghan Markle aren’t messing around.

Now the royal and the Suits star are crossing off another very important relationship landmark that signifies how serious they are: the official plus one.

With Prince Harry playing best man at old friend Tom “Skippy” Inskip’s wedding to Lara Hughes-Young this weekend, the 32-year-old has invited Meghan as his date to the lavish three-day event so they can spend quality time with his “crew”.

According to the Daily Mail, the fun-loving royal has already arrived in Jamaica with Meghan due to fly in from Toronto shortly.

Harry and Meghan are set to spend the weekend surrounded by the royal’s friends in Jamaica.

And while Prince Harry reportedly flew premium economy on a Virgin Atlantic flight to Montego Bay, the actress – whose love of a gifting suite was revealed earlier this week – is said to be arriving via private jet.

“This the first time that she and Harry have socialised so openly as a couple and is a significant step up in their relationship,” one source told the publication.

Harry has already arrived at the tropical island in preparation for the three-day festivities.

According to the report, Meghan is said to have met Tom and Lara during her recent stays in London, and “get on well” with the couple.

“Make no mistake, [Harry] is heads over heels about her,” adds the source. “This one could go all the way.”

Known to have been Harry’s wingman during their party-hard days, Tom is one of the last to marry of the group. However with the wedding taking Tom off the market, Harry is the last man standing when it comes to avoiding the aisle.

Harry and Tom are old friends, with the two reportedly hitting the party scene hard in their bachelor days.

But that might not be the case for much longer, following news he’s preparing to pop the question in just a few short months.

“They will be engaged by the end of [US] summer,” a source told Us Weekly. “[They] have spoken candidly about their future. They see a life together.”