Sarah Michelle Gellar is mourning the loss of her best friend, Shannen Doherty.
The “Buffy the Vampire Slayer” actress, 47, posted an emotional message on Instagram Monday, two days after Doherty died of cancer at age 53.
“How do you possibly find the right words to sum up 30 years of friendship?” Gellar began her post, which included photos of the pair from over the years.
“I keep reminding myself it only hurts this much because, there was so much love,” she continued. “Thank you, for all your kind words and support. I love all the messages about how @theshando was important to you. So let’s honor her.”
Gellar went on, “More than anything, Shan loves animals, especially dogs. In her memory let’s support our favorite animal charities. Whether that’s donating money , stopping by your local shelter and just offering cuddles and walks to animals housed there or even just tagging them in the comments so other people can learn about their work. I know that would make our girl happy (and illicit that deep throaty laugh we all loved).”
In the comments, Gellar tagged the Lange Foundation, a nonprofit pet rescue and adoption service located in Los Angeles.
Doherty lost her battle to cancer on Saturday. She was initially diagnosed with breast cancer in 2015, enduring a mastectomy, chemotherapy and radiation. She went into remission in 2017, but in February 2020, shared she was battling Stage 4 breast cancer.
The “Heathers” actress formed a close bond with Gellar when they were starring on the WB shows “Charmed” and “Buffy the Vampire Slayer,” respectively, in the 1990s.
In 2020, Gellar told PEOPLE that she talks to Doherty “every day.”
“She’s amazing,” Gellar said about the “Beverly Hills, 90210” alum.
That same year, the pair interviewed each other for Entertainment Tonight and opened up about their longstanding friendship.
“It’s so nice for me to have a female friend that feels no threat, no jealousy. We have never felt that with each other,” Doherty said to Gellar. “We’ve done nothing but lift each other up and support each other in our careers and champion one another.”
Doherty also revealed that Gellar was one of the first people to find out about her stage 4 breast cancer diagnosis in 2020. She had an oncologist on hand when she shared the news to Gellar and her other closest friends and family members.
“I knew that typically someone like you would have more questions and so for me to have my oncologist be there so that he could answer the questions, to squash any doubts that people had or to comfort, I think it was really to help you guys,” Doherty said in the interview.
Gellar said she learned to not be afraid to ask questions about Doherty’s cancer battle.
“You never know as a friend, as family, what is your place, what are you supposed to do?” she said.
Gellar supported Doherty during the latter star’s cancer battle. Last year, the “Cruel Intentions” star called Doherty a “warrior.”
“She’s incredible. She lives every day and she’s fighting,” Gellar said to Access Hollywood. “There are ups and downs and there are days that are harder than others and there are some days that are easy, but she’s doing great.”