Help! PJ, now 10 mos. old, has started barking in the middle of the night. He has always slept in his crate without a problem. Usually if either one of them yips in the middle of the night, its a bathroom emergency, which is not common. For 3 nghts now, PJ has barked, but doesn't have to go, and then just keeps barking. Tonight it started at 11 p.m. and he kept barking for about an hour, then was quiet for a while ( 15 mins maybe) and then started in again. He was getting pretty frantic so I checked him again, made sure his bed wasn't soiled, went outside again (nothing) and put him back to bed. He has been yipping on and off (mostly ON) for over an hour. Their crates are in the kitchen (poor Abby...she hasn't made a peep) and that's where they've always been. We're at our wits end, not to mention exhausted after 3 nights of this. Other than this, his behavior is fine and normal, appetite normal. Any suggestions?