Parental Rights vs. Best Interest of the Child

I don't know about y'all, but this whole "best interest of the child" thing seems like it could get out of hand quickly. I understand that some parents are terrible at their job, but where will the government draw the line??

If you haven't heard about the Illinois Mom, go to the following link. All I can think is, "It could have easily been me." I am not an irresponsible parent (most of the time), and I have Seth and Leah's best interest at heart. But... would a prosecutor agree?

http://www.myfoxmemphis.com/myfox/pages/Home/Detail?contentId=6027229&version=1&locale=EN-US&layoutCode=TSTY&pageId=1.1.1&sflg=1