“The Crown” star Vanessa Kirby — who played Princess Margaret on the hit Netflix show — and professional Lacrosse stud Paul Rabil are engaged ... posted cute pics and a heartfelt message ...

The Crown star Vanessa Kirby is engaged to lacrosse legend Paul Rabil ... it Instagram official when Rabil - known as "the LeBron of Lacrosse" - posted cute pics and a heartfelt message.