At the start of the film, they meet in a restaurant for the first time. Yet on the way to the hospital, they refer to a previous trip. In the footage of everyone jumping into the water, it's all the same faces that supposedly just met. * EDIT - they referred to a previous trip & then *all of them that just met* went jumping into the water. They talked about doing it & then they did it. Not a goof.
Charlotte keeps looking to the side when the group is in front of the hospital. She is obviously responding as she smiles at whoever it is.