Princess Eugenie is mourning the loss of her “special friend,” actor Michelle Trachtenberg. The royal posted a moving tribute to the late actor on her Instagram Story this week. Trachtenberg, 39, was confirmed dead on Wednesday after her mother discovered her in her New York City apartment.

Eugenie became friends with Trachtenberg when she lived in New York City and worked for the art auction start-up Paddle8 from 2013 to 2015. Their friendship first became public in December 2013, when they were photographed courtside at a Knicks game alongside actor Michael K.

News of Michelle Trachtenberg's death prompted tributes from her friends and former "Buffy," "Harriet the Spy," and "Gossip Girl" costars.