Shannen Doherty Reflects on a 'Lifetime' of Friendship with Matthew Perry amid the 'Shock' of His Death 

Shannen Doherty is paying tribute to her former costar and friend Matthew Perry.

Doherty, 52, spoke about her “lifetime” of friendship with Perry in an emotional Instagram post after the actor — who was best known and celebrated for his role as Chandler Bing on Friends — was found dead at a Los Angeles-area home on Saturday in an apparent drowning. Perry was 54.

Sharing a throwback photo of herself with Perry, Doherty wrote: “We were a gang way back. We all grew up together going to the Formosa, North and constantly laughing. Matt, Roger, David, Roxana. We played dare and Matt had to say ridiculous things to girls at the bar. We just always had fun and supported each other.”

In the photo the actress — who is currently battling stage 4 breast cancer — shared, she and Perry smiled as they sat on a bench together with another friend.

“You would always find us all together in a booth speaking in our own made up language. And yes, Matt always had THAT sense of humor,” she continued in her heartfelt message.

Doherty — who starred alongside Perry in an episode of Beverly Hills 90210 in 1991 — also revealed in her tribute post to the actor that the pair once went on a date in Malibu, as she shared more about their long friendship.

“Matt and I had a date and it was on Valentine’s Day. He wanted to get a reservation at a restaurant in Malibu but couldn’t so my dad got the reservation for him,” Doherty shared.

“We went and he talked about my dad's Irish persuasiveness the majority of the night. Our friendship spanned a long time. A lifetime really. I know many are hurting, especially our little gang.”

“He will be missed by many and definitely by us. Yes. I could be more poetic or say things better but right now, shock and sadness prevail,” the actress concluded. 

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Perry played tennis ace Roger Azarian opposite Doherty’s Brenda Walsh and the rest of the 90210 gang in episode 19 of the first season of Beverly Hills 90210 back in 1991.

Three years later, the actor would appear in his breakout role as Chandler Bing on Friends, which ran for 10 seasons up until 2004. 

As well as Doherty, many other friends and costars have reacted to the tragic news of Perry's death and paid tribute to the late actor, including Friends costars Morgan Fairchild and Paget Brewster.

Fairchild, who played Perry's character's mom in the hit sitcom shared an emotional post on X (formerly known as Twitter), where she wrote, "I’m heartbroken about the untimely death of my 'son', Matthew Perry. The loss of such a brilliant young actor is a shock. I’m sending love & condolences to his friends & family, especially his dad, John Bennett Perry, who I worked with on Flamingo Road & Falcon Crest. #RIPMatthew"

Brewster also honored Perry on the social media platform, in a post where she described him as "lovely" and urged her followers to read his memoir, Friends, Lovers, and the Big Terrible Thing.

"I’m so very sad to hear about @MatthewPerry," Brewster wrote on X . "He was lovely to me on Friends and every time I saw him in the decades after. Please read his book. It was his legacy to help. He won’t rest in peace though.. He’s already too busy making everyone laugh up there."

According to TMZ, first responders were called in for a cardiac arrest at the L.A. residence on Saturday. The outlet also reported that Perry was found in a jacuzzi at the home and that no drugs were found and no foul play was involved.

A spokesperson for the Los Angeles Police Department told PEOPLE that officers responded to a call at Perry's address regarding the death of a male in his 50s. The deceased individual's identity was not confirmed. 

A statement from Warner Bros. TV, which produced Friends, was issued on Saturday: “We are devastated by the passing of our dear friend Matthew Perry. Matthew was an incredibly gifted actor and an indelible part of the Warner Bros. Television Group family. The impact of his comedic genius was felt around the world, and his legacy will live on in the hearts of so many. This is a heartbreaking day, and we send our love to his family, his loved ones, and all of his devoted fans."

Representatives for Perry did not immediately respond to PEOPLE's request for comment.