JetBlue Airways will ask passengers flying with emotional support animals for more documentation about the animal's health and behaviour, citing "health and safety risks" from an onslaught of untrained animals in its cabins. The airline joins competitors American Airlines, United Airlines and Delta Air Lines, which issued their own, stricter emotional support animal rules earlier this year. Starting July 1, JetBlue will require passengers traveling with such animals to notify the airline 48 hours in advance and provide a medical or mental health form from the doctor who prescribes the animal and another from a veterinarian stating the animal's "fitness to fly" and vaccination records. The airline will only accept emotional support dogs, cats or miniature horses. <br/>