Daniel Radcliffe Remembers 'Incredibly Funny' Robbie Coltrane: 'Very Sad He's Gone'

Daniel Radcliffe is still mourning the loss of his former Harry Potter costar Robbie Coltrane.

During an appearance on Monday's episode of Watch What Happens Live with Andy Cohen, the 33-year-old actor shared his favorite memories of working with Coltrane, who died on Oct. 14 at the age of 72.

"Robbie was amazing at keeping us, particularly when we were very young, entertained," said Radcliffe, who spent a decade working with Coltrane over the course of eight Harry Potter movies. "Those early films were just about keeping a lot of 10-year-olds up and ready. So he was cracking jokes, incredibly funny."

One particular moment, during the making of 2004's Harry Potter and the Prisoner of Azkaban, stood out in Radcliffe's mind.

"There was period on the third film where we were getting horizontal rain. We were supposed to have been there for three weeks — we ended up being there for six weeks. And we just sat around in Hagrid's hut and he'd be telling jokes to us all and the crew that were in there, was well," Radcliffe said. "It was very lovely."

"Very sad he's gone," Radcliffe added.

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HARRY POTTER AND THE SORCERER'S STONE, Robbie Coltrane, Daniel Radcliffe, 2001
HARRY POTTER AND THE SORCERER'S STONE, Robbie Coltrane, Daniel Radcliffe, 2001

Warner Brothers/courtesy Everett Collection Robbie Coltrane and Daniel Radcliffe in Harry Potter and the Sorcerer's Stone (2001)

RELATED: Daniel Radcliffe Remembers Late Harry Potter Costar Robbie Coltrane as a "Lovely Man": "Very Sad"

Coltrane immortalized the role of Rubeus Hagrid in the films. The Hogwarts keeper of keys and grounds, who also happens to be a half-giant, is the first person Radcliffe's Harry meets from the Wizarding World before setting off to Hogwarts.

Over the course of the epic tale, he became a mentor of sorts for the boy wizard, as well as his two closest friends, Hermione Granger (Emma Watson) and Ron Weasley (Rupert Grint) — and it's a relationship that Radcliffe fondly remembers offscreen.

Upon Coltrane's death in October, Radcliffe shared his affection for his late costar in a statement to PEOPLE, raving about how he felt "incredibly lucky that" he "got to meet and work with" Coltrane.

"He was an incredible actor and a lovely man," Radcliffe said.

Robbie Coltrane and Daniel Radcliffe
Robbie Coltrane and Daniel Radcliffe

Alan Davidson/Shutterstock Robbie Coltrane and Daniel Radcliffe in 2002

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Coltrane's agent and friend Belinda Wright confirmed the news of his death to PEOPLE Oct. 14, sharing that he died that day and calling the actor "a unique talent."

"He will probably be best remembered for decades to come as Hagrid in the Harry Potter films, a role which brought joy to children and adults alike all over the world, prompting a stream of fan letters every week for over 20 years," Belinda continued.

"For me personally I shall remember him as an abidingly loyal client ... as well as being a wonderful actor, he was forensically intelligent ... brilliantly witty," she added. "And after 40 years of being proud to be called his agent, I shall miss him."

The actor died in Larbert, Scotland, in a hospital close to his home, Deadline reported.

Multiple organ failure led to Coltraine's death according to a death certificate obtained by the Daily MailTMZ and the Daily Mirror, who noted too that he had been suffering from heart blockages, sepsis and a lower respiratory infection.

Additionally, the actor had previously been diagnosed with type 2 diabetes, according to his death certificate.

RELATED: Celebrating Robbie Coltrane's Beloved Character Hagrid: "I'll Not Be Here Sadly, but Hagrid Will"

In the Harry Potter 20th Anniversary: Return to Hogwarts, which aired on HBO Max earlier this year, Coltrane emotionally reflected on his time as Hagrid in the films, which were released between 2001 and 2011.

"I just think it's an end of an era. It's 10 years of my life, my children have grown up during it," he said.

"The legacy of the movies is that my children's generation will show them to their children, so you could be watching it in 50 years' time, easy," he continued in the special.

"I'll not be here sadly, but Hagrid will. Yes," Coltrane added.