Other mistake: Under the Gazebo when Penny is giving a lesson to the group, the opening shot is zoomed in on people's feet. The 5th person is a lady wearing red kitten heels. When the picture zooms out to show the entire group, the lady with the red heels is gone. (00:04:40)
Other mistake: When Johnny breaks his car window, he is getting soaked but Baby is completely dry - her coat never gets wet.