The heir is not allowed to go into the house and start taking items belonging to girlfriend.  The owner of the property has to follow proper eviction procedures which include 30 day notice.  Only the sheriff's office can evict.  The girlfriend should contact the local district attorneys office and complain that the property owner is attempting to evict without proper notice and also entering the premises without permission.  The trouble is that without a lease or other documentation, the girlfriend is going to to be somewhat less protected.