Deductions & credits

Thank you Critter-3.  I know I sound a little confused about this but I just want to be careful not to make a mistake.  Yes, I understand my step child is my child, no question about that.  The "grandchild" in question is not my daughters child but a child her husband already had when they got married.  Am I still ok to claim her as a dependent? We meet all the other requirements.