From an interview with Bruce Campbell:
When did you first meet the Raimis?
I was born in the same hospital as Sam Raimi – the William Beaumont Hospital in Royal Oaks.
I met Sam in junior high – very briefly while I was with a friend of his – and he was dressed as Sherlock Holmes, playing with dolls. I thought he was a creepy weirdo, and I avoided him, officially, until drama class in high school, in 1975.
Sam was very much into magic, and I was his assistant at a couple of magic shows. Then, I think Sam made a logical transition into film being the ultimate sleight of hand.
And this is what – late '60s, early '70s?
Well, for Sam, I think he started doing home movies in the early '70s. I did them in the early '70s, and we started making – then I met other guys in our neighborhood who had been making Super-8 movies longer than us, Scott Spiegel being one of them.... Josh Becker, who was Sam's neighbor...
... so there was a weird group of about six of us, who wound up teaming up and making Super-8 movies on weekends – almost every weekend.
and
So, around this time, is it a bit apocryphal that you also babysat for the Raimis?
- Well, I took Ted [Sam Raimi's younger brother] to cello lessons occasionally, but I think they made me do that because I ate dinner over there all the time.
Just out of convenience, because you were always filming?
- Yeah. We'd shoot in Sam's living room, and eat dinner, and then whenever the Raimis were working and Sam was busy I'd pick up Ted at cello lessons. I think I've known Ted since he was about 9.
So,
- Sam Raimi and Bruce Campbell have known each other since High School
- They started making movies together in the 70's.
- Bruce Campbell visited the Raimis so often they used him as a babysitter for Sam's younger brother ;)