My daughter is sixteen, and I swear, all that comes out of her mouth is whining and begging. It's gotten worse, despite us trying to fix the problem. We have her repeat her sentences until she can say something without whining, take things away, and have grounded her on days where it's particularly bad, among several other things. Lately, it's been terrible because she's acted up terribly and we've grounded her. She is extremely hard to reason with. Any suggestions as to how to break this habit?