It is time for the madness known as Dysfunctional Family Christmas. If you don't believe me, go find a law enforcement officer and ask. Go to the local family court and ask. Go to child protective services and ask. Go to department of human services and ask.
There will be basically two types of cases when it comes to grandparents starting to raise grandchildren, aunts and uncles raising nieces and nephews, cousins raising cousins. One will be abandonment. The other will be neglect. The stories will sound similar. The outcomes will hopefully be in the best interest of the children involved.
Remember that I am just another relative, a grandparent raising grandchildren; not an attorney, not a law enforcement officer, not a social worker; just another person who has been through the muck and mire of the process. I will explain, based on what I've gleaned from fact-based places and not tirades, what you might need to successfully walk through the process of temporary custody.
If you need this information, make sure the printer works or that you have pen and paper at the library or Internet cafe to take notes.