Go to the scene where Beethoven gets in bed with George (the dad) after George goes downstairs to find the tv on. When George goes upstairs, Beethoven is in his bed, George not noticing, thinks it's his wife. When George talks to who he thinks is his wife, he says, "You alright? You're quiet." The camera is focusing on Beethoven as he says this but if you look, you can just see half of George's face, and you can see his lips. When he says this line, his lips don't move one bit. I found this mistake quite funny.