Sarah Michelle Gellar, Taylor Momsen and Blake Lively are among those paying tribute to Michelle Trachtenberg, who died Wednesday. Trachtenberg was found in her New York apartment “unconscious and unresponsive,

Time passes. You take for granted you get the chance to see an old friend. To paraphrase, the real tragedies in life are the ones that blindside you on an idle Tuesday,” Lively wrote

Gossip Girl star Taylor Momsen said her 'heart was on the floor' as she paid tribute to her close friend Michelle Trachtenberg