Jennie Garth, Tori Spelling and More Beverly Hills 90210 Alums Pen Heartfelt Tributes to Shannen Doherty

Both Jennie Garth and Tori Spelling took to Instagram Sunday after Doherty's passing Saturday following a years-long battle with cancer. She was 53-years-old.

"I am still processing my tremendous grief over the loss of my long time friend Shannen, the woman I have often described as one of the strongest people I have ever known," Garth wrote alongside a set of photos of the pair from their 90210 days. "Our connection was real and honest. We were so often pitted against each other but none of that reflected the truth of our real relationship which was one built on mutual respect and admiration."

"She was courageous, passionate, determined and very loving and generous. I will miss her and will always honor her deeply in my heart and in my memories," the actress continued, making mention of those Doherty left behind, including her beloved pup, Bowie. "My heart breaks for her family and Bowie and all the people who loved her. 💔."

Spelling, meanwhile, shared a more recent photo of her and the Charmed actress on her Instagram Stories as she struggled to find "outward words" to describe the grief she was experiencing amid the news of Doherty's passing.

"I don't have outward words yet...but WE knew and that's what matters," Spelling wrote alongside a slew of broken heart emojis.

She later posted to her grid with a more heartfelt message for Doherty, sharing photos of the pair throughout the years, from their time filming 90210 and and some off-screen moments.

"F--k them… is what Shan would say if I told her I felt pressure to have to summarize via social media a 36 year relationship and the grief I feel for a fire who’s flame went out too soon. I was 15 when Shan and I met. I was the boss's daughter with no voice and she was the star with a big voice. She took me under her wing. She gave me the belief I had a voice and was worthy," Spelling wrote. "We became fast best friends. We were each others wing women, true confidantes, support systems navigating bad relationships, roommates of sorts at times, travel buddies, and so much more. She always stuck up for me. Always had my back. Always believed in me when I didn't or couldn't believe in myself."

She continued, "We were young. We let a lot of outside and inside influences influence our friendship. In a world where we often don't get to make up with the childhood friendships that formed so much of the adult you become, we got that chance. I'm grateful @theshando and I got to go back in time as adult friends and remember why we truly loved each other to begin with. To reminisce. And, to iconically laugh again like we used to. No one could make me laugh like that. Core laughs!"

"She was a rebel in an era when most women didn’t feel comfortable being strong. She never tried she just was," Spelling added. "She empowered sexiness, strength, 2 f--ks given, empathy, and all topped off with wicked humor! Her sardonic humor was one of my faves. And, no one made a frito pie like Shan! Shan… I’ll carry the torch on. Take on my power! And, Ill stay rebellious for you. Love you with all my heart. Always. 🖤💔."

Beverly Hills, 90210 alum, Jason Priestley also paid tribute to Doherty, writing, "Shocked and saddened to hear about the passing of my friend Shannen. She was a force of nature and I will miss her. Sending love and light to her family in this dark time," with fellow 90210 star Gabrielle Carteris penning an Instagram post that read, "So young - so sad. May you RIP Shannon. I know Luke is there with open arms to love you."

Brian Austin Green also paid tribute, sharing a post on his Instagram Stories. "Shan. My sister ... .. You loved me through everything. You were part of my understanding of love. I'll miss you more than I know how to process right now. Thank you for the gift of you 💔💔."

On Sunday, Doherty's rep, Leslie Sloane, announced the news of her death.

"It is with a heavy heart that I confirm the passing of actress Shannen Doherty. On Saturday, July 13, she lost her battle with cancer after many years of fighting the disease," Sloane said, per TMZ. "The devoted daughter, sister, aunt and friend was surrounded by her loved ones as well as her dog, Bowie. The family asks for their privacy at this time so they can grieve in peace."

The late Luke Perry's daughter, Sophie Perry, 24, also honored Doherty with a post on her Instagram Story, sharing a throwback photo of the former co-stars.

The photo sees a glam shot of Doherty and Perry -- who played love interests Brenda Walsh and Dylan McKay on the teen drama -- with Perry holding Doherty's necklace between his teeth. Sophie added a simple white heart emoji to her post.

Doherty was first diagnosed with breast cancer in 2015. While she was believed to be in remission in 2017, in 2019 she learned her cancer had metastasized as Stage 4 in her brain and bones. Late last month, Doherty shared on her podcast Let's Be Clear that she started a new round of chemotherapy. Despite being told that her Stage 4 cancer was incurable, she shared that she felt "hopeful" and was maintaining a positive outlook.