The Design and Implementation of laffer1

http://www.cnn.com/2009/US/02/11/missing.florida.girl/index.html 

Anyone who's been in a mobile home knows the rear door is a joke.  Most of them can be easily opened depending on the weather without signs of "forced entry".  However, I would be suspect of the girlfriend if she didn't want the daughter in "their" life.   Without knowing the situation, it's hard to say.  

When I was living in one of those tin cans, I had a friend who snuck in a few times using the rear door during the summer.  If you held the knob a certain way, you could literally open the door without any serious trouble.