Speaking on BBC’s Radio 4 Today programme, The 81-year-old – who played Professor Sprout in the fantasy franchise – spoke about her former co-star, who died yesterday aged 72.
“I didn’t know he was ill. He just put on too much weight, stupid boy!” the British-Australian actress said on the radio show.
“That’s the problem, he loved to drink. I used to wag my finger at him.”
“It’s such a waste to think of all that talent, that fire, he acted with passion. He was really wonderful,” she added.
Despite her good-humoured nit-picking at Coltrane’s lifestyle choices, she insists that her late friend and co-star “had a heart of gold”.
“Huge in stature, in personality, in heart. He was exceptional,” she continued.
Margolyes played Professor Sprout, the Herbology teacher at Hogwarts, in two of the films while Coltrane was known for playing the gentle giant, Rubeus Hagrid.
Several other heartbroken Harry Potter stars gave their condolences after hearing the tragic news yesterday.
Leading man Daniel Radcliffe gave a heart-warming statement remembering Coltrane yesterday, thanking him for “keep(ing) us laughing constantly as kids on the set”.
“I’ve especially fond memories of him keeping our spirits up on (2004’s Harry Potter and the) Prisoner of Azkaban, when we were all hiding from the torrential rain for hours in Hagrid’s hut and he was telling stories and cracking jokes to keep morale up,” said the 33 year-old actor.
Radcliffe said he “feel(s) incredibly lucky that” he “got to meet and work with” Coltrane, adding that he’s “very sad that he’s passed.”
“He was an incredible actor and a lovely man.”
Emma Watson, who played Hermione Granger, also offered her thoughts on Coltrane’s death.
“Robbie was like the most fun uncle I’ve ever had but most of all he was deeply caring, and compassionate towards me as a child and an adult,” Watson said in a statement on Instagram.
“His talent was so immense it made sense he played a giant – he could fill ANY space with his brilliance.”
“Know how much I adore and admire you. I’ll really miss your sweetness, your nicknames, your warmth, your laughs and your hugs. You made us a family. Know you were that to us.
“There was no better Hagrid. You made it a joy to be Hermione.”
Other Harry Potter alum also paid tribute, including James Phelps, Bonnie Wright, and author JK Rowling.