I think the brother factor makes the Angels reluctant to trade Jeff Weaver, that and the fact that not many teams are going to want his salary for a #5 starter. I think the ANgels signed Jeff so that when they drafted Jered, he'd be inlcined to sign.
In a few years, trading Jeff probably won't effect Jered, but for a rookie, it might cause problems...
Besides, Jeff has actually looked better and better ever since Jered showed up. Maybe getting shown up by his little brother was just the thing he needed.
Jeff has had the curse of great expectations unmet for most of his career. Detroit started him way too young but he flirted with good stuff, and when he went to Yankees, the thinking he was on the verge of greatness, didn't happen.... but then unnoticed, he actually put together two pretty solid years in LA., but was hampered by low run support and occassional mental lapses where a bad homer or inning would distract him and he didn't recover.
But I'm noticing he's shaking off those bad mistakes and getting back to what he was doing right more and more.