Today, I noticed my little budgie has poop on his vent. I noticed it after he was continuously scratching it with his feet. This morning, he had diarrhea-like poop on his ladder. He has acted normal otherwise- bobbing, tweeting, eating. He is close to a year old, so I doubt if he has any problems. Is this possibly due to him having an upset stomach last night? I don't remember this happening before. I appreciate any replies.