J.,
I think it's great that you are consistent with the discipline. It's really important to give toddlers structure and routine, but have you explained to her why it's wrong?
This was something that was pointed out to me by the therapist my ex and I were seeing...she explained that the word 'no' means nothing to a toddler without some kind of back-up. Her theory is that you can say 'no' and 'redirect' the behavior away from the 'bad' and then if they repeat it follow-up with punishment, but 'no' without some kind of reasoning is pointless. I can tell my son 'don't do that' but, there is no reason for him to stop. The example she gave us, was 'don't throw those blocks, you could hurt someone or yourself. let's play with them like this' and then show how to use them...if they behavior repeats, then take them away and explain why and what the consequence is...this has worked really well with my son.
Just a thought.
But, as for the hubby...he NEEDS to get with the program. If you are living seperatly you need to be on the same page, but disagreements need to be done away from your little one. Kids can sense dissention in the ranks, and this can create confusion and tension. Sit down with him and explain to him that you appreciate his input, but at this time this is the path you have chosen to take. But, understand that he should be allowed to give input on his daughter's discipline and care, and he will most likely voice his opinion. It is of course up to you how you handle it, but try to work these details out away from her.
With my ex, I would simply say to him something like 'your input his helpful but not right now' and continue with what I was doing at the time.
Be firm and clear with him...just like you are with your littl girl.
Good Luck.