H.L.
Hi there. I just learned about this website so I am a little late in responding to your initial post :)
I have read the other posts and think you have gotten some good responses. We had the same problem with my son and I finally learned how to get him to stop. To this day he is 4 and still has days where he is just extra tired from a long day and we have to just give him extra love and mercy. But I had to realize that on days that he was only doing this to be a brat, I learned from the help of friends with great behaved children that it was much deeper than that.
You need to gain the respect of your daughter. She is throwing tantrums because she can and she gets away with it. You can train babies to stop crying whenever you want them to, so you can certainly train a 17 month old. We had to learn to just put him in time out and lovingly tell him that this is inappropriate and that he isn't going to get up until he stops crying, that Mommy and Daddy loves him but I won't listen to him cry. Then I left him. If he got out, I put him back, and just like on Super Nanny, it works. She won't do it very long if you gain her respect now by training her she is the child, and you are the mom. She needs to respect you and your authority, with love and firm consequences (time-out). Pretty soon you'll be home free and you will all be much happier.
a website you might enjoy with great parenting skills is www.nogreaterjoy.org They have tons of people who write in with questions and need advice on parenting. These people who run this website have changed my entire life as a mom thru their books and their teaching. Now my 2 kids are MUCH happier children! Not to mention me :)
H.~