Please help save Bruno's leg

My baby boy got away from the sitter and found his way 30 plus blocks toward my work. He managed to get onto the 205 freeway at 92 nd and flavel. He was then hit and the driver left the scene. He was thrown off the freeway overpass where he was then hit by a second vehicle. With a broken leg and in shock he took off running and it took police and animal control 2 hours to find him. Once taken to the hospital I spent the only 3000 dollars I had available to make sure he made it through the night. Unfortunately without treating the compound fractures in his leg he would have to be put down. Medical expenses to amputate or save the leg ranges from 2500-5000 dollars. Please help me through this painstaking event. I can't lose my boy. Any financial aid would be a god send. Please help save bruno