My DD, who just turned 4, is lovely and exuberant at times, but she is also really whiney and negative. At least 3 or 4 times a day she'll have a strop about something. She just came back from a friend's b/d party and said with a mardy face that it was no fun. Then I showed her the dress I'd bought her and she said she didn't like it. Will this kind of stuff change? Is it normal for a 4-year-old, or does she (I hope not) just have a negative personality? Is there anything I can do to make it better, except trying to be cheerful myself?