My boyfriends mom came over and told me only immediate family could see him and since we aren't married , I can't see him but our son can go along with them to the visit, is it true only immediate family can visit ?

Some places have restrictions for certain situations but this is not the norm. If you are the mother of the inmate's child, we doubt very much there is a prison or jail in this country that would stop you from visiting. We would recommend calling the facility and speak with a counselor or case manager to get the straight story. If that doesn't work, call the warden's secretary and tell them your situation. You will get in there.