Can anyone offer tips for a skinny 4 year-old? Every time I look at her, her behind is sticking out. We've tried Gap and Old Navy and Gymboree jeans. I've cinched in waists to the point of being uncomfortable, but they still fall down. Does some brand make a higher rise? I don't want to put her in "mom" jeans, but it's hard to teach modesty when your behind is sticking out.