the lesser brother is always slightly disliked and considered a nepotism beneficiary
Jim Belushi
Brian Doyle Murray
Randy Quaid
Zeppo Marx
Reginald McDonald
etc.
In Jim's case I believe it was stephen colbert on the strike force five podcast that told the story of Jim liking to pull audience members up on stage during improv shows and slap them,,,,,he said he would do it hard and the combination of the shock and them being in front of an audience would make it so they never slapped him back..
So one show, it happened and Colbert improv'ed a bit were he slapped Jim back hard and then encouraged the guy who got slapped to do it to. Think he said him and Jim had some heated words backstage after that one
thus Stephen > Jim
I think one of the other hosts talked about Jim getting into a pretty heated exchange with like Mr. T or some other tough guy of the era......So I think young Jim may have been a bit of a cocky douche