Continuity mistake: When all the guys enter the apartment with the doctor lying on the couch, John's carrying the Biophone with his right hand and starts to place it down, but then it cuts to another angle and John's holding the Biophone in his left hand as he places it down.
Continuity mistake: After Early tells Dr. Ned that he thinks he has mononucleosis, when Early leaves the room, the nurse that's in the room with Dixie walks away from the patient to the other side of the room, but in Dr. Ned's closeups that nurse is still standing behind him while he talks to Dixie.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.