We've been very lucky up to this point and haven't really needed to do any sort of disciplining, but DS turned 2.5 a few weeks ago and instantly all hell broke loose Not listening, total defiance, talking back, screaming tantrums, laughing at attempts to discipline, etc. We'd like to start some kind of timeout routine, but I honestly have no idea where to begin. And unfortunately when DS acts out, DH turns into a 2 year old himself, so I'm kinda alone in finding a "constructive" way to deal with it.

Any book/article recommendations? Anyone else see a sudden behavior shift at 2.5?