First, when my little girl was just about to turn 2 she had a problem with bedtime. I feel that at that time it was separation anxiety. I reassured her every night that mommy and daddy were right next door and that we were always there for her. I did this over an over again at bed time. I also put a couple of stuffed animals in her bed to keep her company. I made a really bid deal out of them being there for her. It seemed to work.
BUT, now, at 28 months old, Hadlie, started the same sleep problems you have been having. She has pretty much always been great at bed and nap times so needless to say it was horribly frustrating.
Hadlie would not stay in her room. She would cry and cry. She would stand in the hallway or come into the living room. She would wake up in the middle of the night and come and get in our bed (we do not allow this as I end up getting NO SLEEP). My husband and I were at our wits end. I was crying hysterically every night because I just couldn't take it anymore. He and I were fighting like crazy. It sucked.
I got to the point that I put a gate up across her door (she knocked it down) and then I put a lock on handle so she couldn't open the door. I felt HORRIBLE, but it was the only thing I could think to do. She would cry for at least 30 minutes and then fall asleep. This didn't solve the waking up in the middle of the night though.
Hadlie would also go down perfectly for my mother (she keeps her during the day) and when she had her at night. Every time I was with Hadlie at nap time, she would not nap. IT DROVE ME INSANE. Yes, it is the only relief you get with a toddler!! I live for her nap time on the weekends!
So, here is what I did: I sat her down one night before she went to bed and had a little talk with her. I actually took her in the bathroom and put her on her potty and made her look directly at me. I wanted UNDIVIDED attention.
I had a package of those mini M&M's and I told her step by step what I expected that night and that the next morning she would get "special, special treats" if she was a good girl. After instruction, I gave her 1 M&M. I said:
1. I want you to stay in your room. (gave her an M&M)
2. I don't want to hear any crying. (gave her an M&M)
3. I want you to sleep all night - no waking up and coming into mommy and daddy's room. (gave her an M&M)
I told her that in the morning, if she did all these things she would get these special, special treats. I asked her if she could do it and she said, "yes Mama." I also gave her the choice of having the door cracked open or closed (she chose open) and the choice to sleep on the floor or the bed (she chose the floor). There wasn't a peep out of her.
I kid you not, she followed every instruction and came in the next morning at 6, got in the bed with me and said, "Mama, I sleep all night." I gave her 4 tiny little M&M's that morning and we have been doing it every night since.
Every night I say, "Are you going to be a good girl tonight?" She will (most of the time) say "Yes." And then I ask her what she gets if she is a good girl. She will respond "special special treats."
We have had a couple of nights that she has not been that great and she doesn't get any treats in the morning. This last week has not been particularly good - she has been sick and has been waking up - but it has been 100% better. She also chooses to sleep on the floor every night but before we go to bed, we put her in her bed.
I don't even give her the treats every morning now. When she asks I make sure to give them to her or if she has had a few bad nights then I make sure to give them to her after the first good night she has. I hope to eventually go to a star chart when she is a little older and we can give a bigger reward at the end of the week, I just don't think she is quite ready for that long of a wait.
This may be the complete wrong approach, but I needed instant relief. My husband is not happy that I am giving her M&M's in the morning. But, hey, desperate times call for desperate measures. You also don't have to use candy, just something that he will want to work for.
Don't try to reason with your son when he is already in bed and crying - prep him all day and see if you can also use the reward system at nap time.
Hang in there. I know how horrible it is, especially when you are used to a good sleeper. I am also due with #2 in February and I can't imagine having to be up all night with two crying babies!!
I hope this at least gives you some ideas. Just think outside the box and come up with something that works for you!
M.