Endless Loop?

Hi again... Having another problem with the same macro that has been giving me trouble for a week now. Now, the macro will run, but after it finishes, excel stops responding. Is this because the macro continues to run indefinitely? Any ideas?

Sub ParseInputToWorksheets()

    Dim memberLists As Workbook
    Dim chapterColumn As String
    Set memberLists = ActiveWorkbook
    chapterColumn = "B"
    
    Dim newMembers As Workbook
    Dim newMembersFilePath As String
    newMembersFilePath = "C:\Creeds\Database\SAE\NewList.xlsx"
    Set newMembers = GetObject(newMembersFilePath)
    
    Dim r As Range
    For Each r In newMembers.Worksheets(1).Rows
        Dim chapterName As String
        chapterName = r.Cells(1, chapterColumn)
        Call CopyToChapter(chapterName, r)
    Next
    
End Sub

Private Sub CopyToChapter(chapterName As String, r As Range)
    Dim memberLists As Workbook
    Dim ws As Worksheet
    Set memberLists = ActiveWorkbook
    For Each ws In memberLists.Worksheets
        If ws.Name = chapterName Then
            Dim iRow As Long
                iRow = FirstEmptyRowIndex(ws)
                r.Copy (ws.Rows(iRow))
            Exit Sub
        End If
    Next
End Sub



Private Function FirstEmptyRowIndex(ws As Worksheet) As Long
    Dim firstCell As Range
    Set firstCell = ws.Range("A1")
    Dim iRow As Long
    iRow = 0
    Do
        iRow = iRow + 1
        If firstCell.Offset(iRow, 0).Value = "" Then Exit Do
    Loop
    FirstEmptyRowIndex = iRow + 1
End Function