Why is my ipod nano showing up in itunes device, but neither my iphone nor my mother's iphone are showing up?! Very irritated.
Do you still have the "Music Video" Smart Playlist in iTunes? If you right click on a video file, which normally shows up under "Movies" you can pick the video type of Movie, Music Video, or TV Show. When you select "Music Video" the video file drops out of the Movies section and if the Music Video playlist is present will show up there.
You might have deleted that playlist so it wouldn't be on the iPod either.
So create a Smart Playlist where the rule is Video Kind IS Music Video...