Exactly. It's illegal for a 16 year old to have a gun in the car alone with her regardless of whether or not it belongs to someone else, is locked up, etc. Kind of like drugs: if it's illegal for you to have them then you can't pull the "I didn't know they were in here" or "oh those aren't mine"...
Are you sure? I'd think it could be a big deal. So you're saying that as long as my kid's car is in my name then he can carry a gun under his seat? I don't think so...