[AccessD] Checkbox/Combo box questions

I think I'd start with many-to-many tables to capture the info.

Something like this might work although I haven't had time to try it out 
yet.:  Having these tables, I'm assuming you can do the coding to 
re-populate the combobox based upon the checkbox selected.

T_Parents
Fields
  ParentID (autonumber)
  PLastName (text)
  PFirstName (text)

T_ParentChild
 Fields
  ParentChildID (autonumber)
  ParentID (relates to ParentID in T_Parents)
  CFirstName (text)
  CLastName (text)

T_UserSelections
Fields:
  UserSelectionID (autonumber)
  ParentChildID (relates to ParentChildID in T_ParentChild)
  UserID (relates to UserID in T_Users)

Penn

P.S. I'm not a well-informed, honored MVP, just a little self-taught coder 
and I put this suggestion out with no little trepidation.  If it helps, 
great.  If I'm completely off base, it won't be the first time, 
unfortunately.