You might be entitled to an emotional support dog in case you have emotional or mental illnesses. Both service and emotional support animals could be excluded from the workplace should they pose either an undue hardship or an immediate threat at work. Moreover, your pet will be in esa letter a position to fly together with you in the cabin of an airplane with no extra price. Emotional Support Animal letters are usually considered valid for a single year. The animal needs to be vaccinated with respect to state and local laws. A companion animal isn’t a pet.