What in the world is up with my kid?

Holland is so into walking (with help of course), but she refuses even to roll over.  Jaret and I spend plenty of time trying to teach her how to do the roll thing.  Then, we put her on her belly and give her the opportunity to practice and she just puts her head down into the carpet and cries.  She doesn't even try and squirm out of the "oh so uncomfortable" position.  Whatever, she must have some bad teachers.  She'll get it eventually. Though, she sure does look cute when we lead her around the house on her two little feet!