Ivan Reitman has described Harold Ramis as his "smarter brother".
The 'Ghostbusters' director worked with late actor on the 1984 classic, its 1989 sequel - both of which Harold starred in and co-wrote with Dan Aykroyd - and other big screen projects, and now he's opened up on their relationship.
He told Empire magazine: "I always thought of him as my smarter brother. He was just very reasonable, very clever.
"And he had a way of writing dialogue quickly and with such dexterity. I was just so impressed with him. When he wasn't around to help me on a film, I really felt handicapped.
"I got to work with him on the first four of five movies that I ended up directing, and we became good, good friends. I think we spoke directly to each other in a very lovely way."
Harold - who sadly died aged 69 in 2014 - played Egon Spengler in the first two 'Ghostbusters' films, and Ivan's son Jason wanted to pay tribute to his dad's late friend as he took over the mantle as director for upcoming sequel 'Afterlife'.
He explained: "The movie is for my father, for my daughter and for Harold. For me, that's it.
"For a long time, I had the idea of a girl finding a proton pack in a barn, walking outside and firing it into a row of corn and popcorn flew out. And I just didn't know what to do with it.
"When Harold passed all of a sudden, I knew who she was: it was Egon's granddaugther.
"The concept of this intergenerational conversation between her and her grandfather became the real roots of what this story what. It became a Spengler story."
There's also the family ties of Jason taking over from his father, and Ivan is proud to see him continue the legacy.
He said: "I think it's one of the greatest gifts a son can give his father. I think his thoughts about the movie and where it could go in the future are so fresh and so exciting. I just feel extraordinarily lucky."
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