Reference parent datacontext binding. / The Lazy Developer

        <Button Content="Reload Reports"
                       Grid.Row="2"
                        Grid.Column="1"
                        VerticalAlignment="Center"
                        HorizontalAlignment="Right"
                        Command="{Binding Path=CommandReloadReports,RelativeSource={RelativeSource TemplatedParent}}" />

<Button Content="Reload Reports"

Grid.Row="2"

Grid.Column="1"

VerticalAlignment="Center"

HorizontalAlignment="Right"

Command="{Binding Path=CommandReloadReports,RelativeSource={RelativeSource TemplatedParent}}" />