programmatically set checkbox in datagridview  to true/false

I have added a datagridview  (DGV) to a windows form.  I programmatically bind it to a data source.   I added a few DataGridViewCheckBoxColumn columns.  I loop through the columns of the DGV until I get to one of the checkbox columns.  I then loop through all rows.   For each Row / Column pair I query a database table using Row and Column information and retrieve a Boolean value.  I set the checkbox cell value to the Boolean value.  When the code finishes and the DGV is revealed, the bound cells are fine but no matter what I set the checkbox cells to (Boolean from datatable info, or 1, or TRUE) it always shows as an unchecked checkbox.  

DGV.Columns.Add(CreateCheckBoxColumn(sNewColumnName, sHeaderText))

Private Function CreateCheckBoxColumn(ByVal sNewColumnName, ByVal HeaderText) As DataGridViewCheckBoxColumn
Dim dataGridViewCheckBoxColumn1 As New DataGridViewCheckBoxColumn()
  dataGridViewCheckBoxColumn1.HeaderText = sHeaderText
  dataGridViewCheckBoxColumn1.Name = sNewColumnName
  dataGridViewCheckBoxColumn1.ThreeState = False
  dataGridViewCheckBoxColumn1.ValueType = GetType(Boolean)
  Return dataGridViewCheckBoxColumn1
End Function

For Each oColumn In Me.DGV.Columns
  If InStr(1, oColumn.Name, "res_", CompareMethod.Text) > 0 Then
     sHeaderText = oColumn.HeaderText
    For iLoop = 0 To Me.DGV.Rows.Count - 1
       sNameAddress = Me.DGV.Item("Fam_nameaddress", iLoop).Value
       bDBase_Value = Me.Tbl_FamilyTableAdapter.IsMemberResourceAvailable(sNameAddress, sHeaderText)
       Me.DGV.Item(oColumn.Index, iLoop).Value = bDBase_Value
    Next
  End If
Next