We've been together for almost 4 years and we live in a rented house. He just left with his sister and did not say where he was going. He didn't leave me any money, food pluse our son was sick and needed to go to the doctor. I know where he is at but his family won't let me talk to him.

You need to go to Court to file an emergency petition for child support.

Apparently he doesn't want to talk to you and isn't going to voluntarily support your child so you will have to take legal action.

You, of course, are not entitled to support because you were not married.