I don't have dogs myself but I'm quite sure what she's doing is either illegal or cruel.
She has one dog of her own and works as a dogsitter for 2 other dogs. Quite regularly she will take the dogs out in the car and leave them in the car for up to 3 hours while her and her DC meet friends in town or visit a museum or shops. She leaves the sunroof open an inch and a bowl of water. Am i right in thinking this is dangerous?