News of Michelle Trachtenberg's death aged 39 prompted an outpouring of tributes across the globe.
The New York police department confirmed her death to HELLO! in a statement on Wednesday.
The police said they responded to an emergency call at around 8am on Wednesday to One Columbus Place in New York and Michelle was later confirmed dead after emergency medical services attended.
The Gossip Girl actress' death is not being treated as suspicious, and the police said the medical examiner will determine her cause of death.
Michelle's passing would have likely come as a shock to Princess Eugenie who crossed paths with the actress during her time in New York back in 2013. Eugenie, 34, travelled across the pond for a new job with auction house Paddle8.
Prince Andrew and Sarah Ferguson's daughter, who now works as a director at art gallery Hauser & Wirth in London, studied English Literature and History of Art at Newcastle University. She subsequently gained experience working at Christie's auction house and the Royal Collection in Buckingham Palace.
The pair appeared to forge a close bond and were spotted socialising together on several occasions. In December 2013, they watched the Atlanta Hawks take on the New York Knicks, while in March 2016, Michelle heaped praise on Eugenie in a touching Instagram post.
"There are few people in life that you meet that you know are true and real. This lady happens to be one of them. Friends really do mean a lot. Happy #stpatricksday May luck of love and friends be with you," she wrote.
Meanwhile, years later in December 2020, the Buffy The Vampire Slayer star alluded to their friendship in a heartfelt post in which she described Eugenie as "one of the dearest, kindest and most genuine friends".
Alongside a wholesome snapshot of the pair grinning from ear to ear, Michelle wrote: "This is a #throwback post. And a dedication to an amazing person. I met this wonderful human. Years ago in New York. Eugenie has been one of the most dearest, kindest, most genuine friends I have ever had in my life."
Reflecting on the COVID-19 pandemic, she continued: "As we are going through these very challenging times. I'm finding new levels of gratitude. I am grateful for the relationships I have made over the years."
When Michelle first wrote about the royal, her words were a celebration of friendship, gratitude and working through tough times. Following her tragic death, however, these words feel even more poignant, akin almost to a farewell message reflecting on the friendships in her lifetime.
It's not known if Eugenie and Michelle maintained their friendship in recent years. Eugenie hasn't issued a statement or spoken publicly about Michelle's passing.