Well, sure, they were all a pretty nasty bunch, even Corwin himself. The question is one of perspective... they all viewed each other as possible resources. And when you have a resource (one of maybe 15 known) who can create worlds inhabited by millions of troops willing to fight for your cause just by walking to them, well... you don't just whack him over a little thing like some plan he might have to stab you in the back and take over once you've won.
Plus, there was the familial love thing going... they were all brothers and sisters, after all.
That's one of the things that got me aggravated. :)
I got tired of these people wussing back and forth between he/she's my brother/sister/enemy. Would they make up their minds already!!! Decide that they're enemy or friend and get it over with. Can you tell I've had it up to here with wussy good guys?
That didn't stop Michael Corleone. :)