Toddler sleep regression?

I am at my wit's end and am going to kill DH (and I think he's ready to kill BabyCrown).  For the last two weeks, BabyCrown has strongly resisted bedtime.  He's been balking at naptime even longer, but I usually just put him in his bed and then shut the door and go downstairs, he'll quiet down eventually and usually gets a decent nap.  DH has been going to him when he gets back up.  Which BabyCrown thinks is hilarious.  DH will NOT let him just be.  Eventually BabyCrown will get upset, and then spend a couple of hours crying in between DH going to him.  DH also refuses to just come downstairs so BabyCrown can't see or hear him.  DH insists on staying up in his office (next to BabyCrown's room) and walking back and forth in front of BabyCrown's bedroom.  So on afternoons when DH has been around to help me (he's working from home at least two days a week right now), BabyCrown hasn't been getting a nap. Which makes bedtime even worse.

Now it seems no matter what I do, BabyCrown isn't going down.  I'm furious with DH because he'll tell me one thing and then five minutes later he's back in BabyCrown's room and then complains to me that nothing is working.  Yeah, because he's being totally inconsistant.

It also doesn't help that the neighborhood kids (the same age as BabyCrown) are outside playing until after nine o'clock at night, and he can hear them from his window (open or shut).

Any suggestions other than I take over bedtime/naptime until I pop in the next couple of days.  I'm terrified by what's going to happen when BabyTiara gets here!!