help with vb.net function return datarow

I have a vb.net app that tries to get a datarow from a function.

Below is the subroutine that calls the function and the function

    Private Sub EmployeeNameComboBox_SelectionChangeCommitted _
    (ByVal sender As Object, ByVal e As System.EventArgs) Handles _
    EmployeeNameComboBox.SelectionChangeCommitted
        ' Find and display territory descriptions for selected employee.

        Dim employeeIDint As Integer
        Dim employeeDataRow As DataRow
        Dim EmployeesRow As DataRow

        Dim territoryDescription As String
        Dim territoryDataRows As DataRow()

        Try
            With Me
                ' Get the employee ID of the selected employee.
                employeeIDint = Convert.ToInt16(EmployeeNameComboBox.SelectedValue)

                ' Find the row from the employee table for the selected employee ID.
                EmployeesRow = .aNORTHWNDataSet.Employees.FindByEmployeeID(employeeIDint)

                ' Retrieve an array of employee rows.
                territoryDataRows = employeeDataRow.GetChildRows( _
                  "EmployeeTerritories2EmployeesRelation")

                ' Fill the list with the array of territory description rows.
                .TerritoryListbox.Items.Clear()
                For Each territoryDataRow As DataRow In territoryDataRows
                    territoryDescription = territoryDataRow.GetParentRow _
                    ("EmployeeTerritories2TerritoriesRelation")!TerritoryDescription.ToString
                Next

            End With
        Catch ex As ApplicationException
            MessageBox.Show(ex.Message)
        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try
    End Sub


The line that throws the exception is

                EmployeesRow = .aNORTHWNDataSet.Employees.FindByEmployeeID(employeeIDint)


Here's the function

 Public Function FindByEmployeeID(ByVal EmployeeID As Integer) As EmployeesRow
            Return CType(Me.Rows.Find(New Object() {EmployeeID}),EmployeesRow)
        End Function






I get object reference not set to an instance of an object