Heartbreakingly, it was Trachtenberg’s mother who found her and made the initial 911 call.

Here are some of the sweet yet sad celebrity reactions tothe tragedy of Trachtenberg’s passing.

Trachtenberg played Dawn, Buffy’s younger sister that appeared in the final three seasons.

Michelle Trachtenberg arrives at the event “Heaven” in Hollywood, CA (2020)

and prayers to her and her family."

You were loved."

James Marsters who masterfully played vampire bad boy Spike also had quite a bit to say.

Danny Strong, Tom Lenk, Emma Caulfield, Alexis Denisof, Alyson Hannigan, Anthony Stewart Head, Joss Whedon, Michelle Trachtenberg, James Marsters, and Nathan Fillion

We have lost a beautiful soul.

Michelle was fiercely intelligent, howlingly funny, and a very talented person."

But it wasn’t just Westwick who was reminding everyonethere was much more to Trachtenberg than met the eye.

Split image of Ed Westwick and Kenan Thompson

Kenan Thompson also took toInstagramto make a heartwarming post.

Check on your people!!!"

But he wasn’t the only casual co-star to pay tribute.

Split image of Rosie O’Donnell and Kim Cattrall

So young, so talented and so sweet!"

She also mentioned just how well the two were able to work together while on set.

And again, Hart is not alone in this sentiment.

Cattrall also responded onX, formerly Twitter, to Variety’s post breaking the news.

There the “Sex and the City” actress wrote, “This is Heartbreaking.

So talented, much too young.”

But she wasn’t the only actress who had fond memories of Trachtenberg.

Rosie O’Donnell, who starred alongside Trachtenberg in the film, toldPeople, “I loved her very much.

She struggled the last few years.

I wish I could have helped.”