It's often a matter of the photographers choice of lens, distance from the model and angle of shot. He most likely went with a longer focal length which would compress the image and in a sense make her features appear a bit thicker or wider looking than they actually are. You want that most of the time with models, but it can go wrong too. That's why people often say the camera adds 10lbs. It's actually true. If you get up close it can distort facial features too much. It's more visually appealing to be back away from the subject about 10-15 feet and use a longer lens so the features of the face are not distorted in an unpleasing way. I can tell that the 2nd picture of her is more of a wide angle lens. You can see more of the background behind her is still in focus. She's got a round face already so she will look better with less compression (widening) of her features.