Facts of Life Stars Julie Piekarski, Kim Fields and Mindy Cohn Mourn Philip McKeon

Nancy McKeon‘s Facts of Life costars are remembering her late brother Philip McKeon.

After battling a longtime illness, Philip died Tuesday morning in Texas. He was 55. Late Tuesday night, Julie Piekarski Probst, who played Sue Ann Weaver on the beloved 1980s sitcom alongside Nancy’s Jo Polniaczek, mourned his death on Instagram.

“The world is less bright tonight,” she wrote alongside an old photo of her and Philip, who was also a child actor. “Nancy, I am so sorry for the loss of your dear sweet brother. I remember all of us in your house in Burbank…laughing and joking around. Philip always had that great big grin that lit up a room!”

“There are no words to take away the pain,” continued Piekarski Probst, 56. “Sending you and your mom hugs. You will be in my thoughts and prayers. Hold on and may you find peace. #loss #family #survival #heavenly #peace #ripphilipmckeon #angel.”

Kim Fields, who played Tootie Ramsey on The Facts of Life, also posted in Philip’s honor on Twitter and Instagram.

“My heart is broken and aches for my sister Nancy who just lost her brother Phil,” wrote Fields, 50. “Please cover her with as much love and comforting grace as you can. You may recall her father just recently passed. While we are grateful there’s no pain and suffering, we feel the hurt, cry the tears and moan in grief. Yes, he was on the show ‘Alice.’ #PhilipMcKeon #RiPPhilipMcKeon.”

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Mindy Cohn, who played Natalie Green, retweeted Fields’ message and posted a photo of Nancy and Philip on her Instagram Story.

“Phil #rip,” wrote Cohn, 53, with a broken heart emoji.

Mindy Cohn/Instagram
Mindy Cohn/Instagram

Family spokesman Jeff Ballard confirmed Philip’s death in a statement to PEOPLE on Tuesday. He is survived by Nancy and their mother, Barbara.

“We are all beyond heartbroken and devastated over Phil’s passing,” Ballard said. “His wonderful sense of humor, kindness and loyalty will be remembered by all who crossed his path in life.”

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Nancy, 53, has not publicly addressed the news, but last month she wished her brother a happy birthday on Instagram while reflecting on the loss of their father, Donald McKeon, who died in October.

“A huge happy birthday to my big brother!!” she wrote. “It’s been a tough time lately… but as we’ve always said…we’ll get through it together…love you Dude….and as always… our humble thanks to all our veterans.”

A source told PEOPLE that Nancy is “devastated.”

“She and Philip were very, very close,” the source said. “The whole family is going to cling together and find comfort in each other during this time. My heart goes out to them.”

Philip is best known for his role as Tommy Hyatt on the CBS sitcom Alice, in which he starred opposite Linda Lavin from 1976-1985.

He went on to work at Los Angeles station KFWB News 98 in its news department for 10 years before moving to Wimberly, Texas, where he hosted his own radio show and relocated to be closer to family. His other credits include the 1987 slasher film Return to Horror High and appearances in CHiPs, Fantasy Island and The Love Boat.