Discharging a family from the Angel Eye system will remove their account and unassign their camera(s). Families are usually discharged when the baby is discharged, or when the camera is no longer available.  

To discharge a family, first click the "Family Accounts" button on the Main Page in the far left menu (Note: The Family Accounts page is the one typically landed upon after logging in, and is what is considered the Main Page):

On the list of families, find the family that you wish to discharge and click the "Discharge from AngelEye" button beside their account: