Recently my mother was on the crosswalk and a speeding driver hit her.?

It was a clear bright sunny day and my mother was out walking. Well when she was crossing at the cross walk, a speeding driver who was chatting on his cell phone hit her in his SUV. From the witness statements, the driver was at fault...I want justice especially for the pain and suffering she is going through. I am at a loss--what do i do now? How do I go about sueing the driver for the accident that he caused? We went to a lawyer and he says that we have to go through my mother's insurance for compensation but this doesn't seem right to me since she was not driving but walking! Help!!!