Before "Seinfeld" super-fan Jim Calder passed away Nov. 7, many of the sitcom's stars brightened his final days with personalized videos and phone calls.

In an article published Tuesday on The Huffington Post, Calder's son, James, chronicled the "amazing story about human kindness," documenting the sweet, funny and moving gestures cast members made on behalf of his father, who died just three days before his 67th birthday after a two-year battle with a rare form of lung cancer.

After James and his wife came up with the idea a few weeks ago to have friends and family wish the increasingly ill Brooklyn native a happy birthday, the couple decided to get more ambitious with their goal.

"We immediately thought of his favorite TV show, 'Seinfeld,'" James wrote. "We started planning how to pitch this to the 'Seinfeld' characters and started to reach out through published articles about the project, social media outreach and word of mouth. The 'Seinfeld' birthday project was born, but we really weren't sure how and if it would flourish."

But flourish it did, and many participating stars delivered their messages to Jim in character. The first to do so was John O'Hurley, who played J. Peterman on the series.

Patrick Warburton, aka Puddy, followed suit.

Wayne Knight (Newman) also said hello.

The spirited videos just kept on coming, including good tidings from Larry Thomas (Soup Nazi), Danny Woodburn (Mickey Abbott), Wayne Wilderson (Walter), Ping Wu (Ping), Richard Fancy (Lippman), Lisa Mende (Carol), and many more.

Even TODAY's own Al Roker, who played himself on the sitcom, sent the super-fan his own show of support.

Other stars opted to check in with Jim in different ways.

Michael Richards, who played Kramer, "wanted to actually call my dad on the day of his birthday to wish him the best and have a chat," James wrote. "I was blown away by his kindness and generosity. I did try to coax him to create a video message as well but he shared that he wasn't interested in the publicity and just wanted to help me wish my dad a happy birthday."

Jerry Stiller, who played George Costanza's father Frank, and Lawrence Mandley, who played Larry the cook, both sent videos in character, but asked that they "remain private for only my dad and our family."

Julia Louis-Dreyfus' video message arrived just hours before Jim passed away.

"I'm so thrilled and happy to hear how much you've enjoyed 'Seinfeld' along with your family; that's a great joy, so thank you for that," the Emmy-winning star told Jim in her video. "You have a wonderful son who clearly adores you, so, congratulations on that; you did that very well. And, third, I just wanted to say happy birthday. I hope it's a great one, and I'm wishing you the very best. Have fun."

Correctly predicting Jim wouldn't live to see his birthday, his son and Jim's wife, Gayle, decided to show him the videos to lift his spirits. "He was shocked and mystified about how we were able to reach the 'Seinfeld' cast members," James wrote. "He really felt the love and support."

Surrounded by family members, Jim died Nov. 7. His obituary in the Bucks County Courier Times describes him as someone who "had razor sharp wit and loved parties, holidays and sharing laughs," adding, "He had kind eyes but a kinder soul and a brilliant mind."

It's been a few weeks since since Jim's passing, but James continues to marvel at the show of support from everyone who helped make the birthday wish possible.

"The amount of kindness shown to my family not just by the actors and actresses but by all the people who read the story was overwhelming," he wrote. "People wrote to me with leads about who they knew and how they knew some of the 'Seinfeld' actors and how the wanted help my family and I reach out to them. Others just sent us beautiful emails about their own families and experiences with cancer."

Brainstorming new ways to raise money and awareness for cancer patients and their families, James asked supporters to make donations in his father's name to the American Cancer Society. In the meantime, he wrote that he's convinced that something that happened the night of his father's death is more than a coincidence.

"My wife and daughter went back to my [parents'] house for the night and my wife just turned on the TV and one of my dad's favorite episodes of 'Seinfeld' was playing," James wrote. "The Merv Griffin Show (season 9, episode 6). We all believe it was a sign from dad as he left this world for a better place."

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