blue jay cough or sneeze ???

[zsunflower03]

weve been caring for a baby blue jay for a few months now. I know should have left him outside but hes been great we let him outside and he flys back in. We recently have been hearing him cough or sneeze alot not sure it started very little now its alot of the time. He eats great , drinks water, flys, and doesnt have any discharge from anywhere. Im calling a couple local people but does anyone have a clue what this could be ?