THE FRIENDLY SKIES — United Airlines is getting tougher on passengers travelling with comfort pets.

From March 1, 2018 all passengers flying with a support animal will show documentation showing their pet has behavioral training and is vaccinated, reports the Chicago Tribune.

Passengers currently travelling with comfort pets need to show they're in legit need of their animal. They have to give United a letter from a mental health professional and 48-hours notice of their plans to travel with the animal.