PONTIAC— Prosecutors made their closing argument Friday, painting Jennifer Crumbley as a distracted parent who didn’t get help for her teen son even though she knew he was in crisis and bought him a gun. Oakland County Prosecutor Karen McDonald went witness by witness, laying out the case against Crumbley, who is being tried on four counts of involuntary manslaughter. She said the trial laid out all the facts to the jury, difficult as they may be, because they “owe it to the victims and their families to say what really happened.” “Listening and watching and thinking about four young kids bein…