Como alterar propriedade de um controle Pai, em evento de objeto filho em WPF?

Question

 <Style TargetType="controls:ModernVerticalMenu" >
    <Setter Property="FocusVisualStyle" Value="{x:Null}"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate  TargetType="controls:ModernVerticalMenu">
                <Grid>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="{TemplateBinding ListWidth}"/>
                                    <ColumnDefinition Width="{TemplateBinding ListWidth}"/>
                                    <ColumnDefinition Width="auto"/>
                                    <ColumnDefinition />
                                </Grid.ColumnDefinitions>


                                <Border Background="{DynamicResource background}" Height="{TemplateBinding Height}" BorderThickness="1" BorderBrush="{DynamicResource bordaSuperior}">
                                    <!-- link list -->
                                    <ListBox x:Name="LinkList" ItemsSource="{TemplateBinding Links}"  
                                             ScrollViewer.HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}" >
                                        <ListBox.ItemTemplate>
                                            <DataTemplate>
                                                <Grid Height="50" Background="Transparent" Width="500">
                                                    <Border Padding="10">
                                                        <Path x:Name="icon" Data="{Binding IconData}" Stretch="Fill" Fill="{DynamicResource Accent}" Width="20" Height="20" HorizontalAlignment="Left" VerticalAlignment="Center" />
                                                    </Border>
                                                    <TextBlock x:Name="texto" ToolTip="{Binding Tooltip}"  Text="{Binding DisplayName}" Margin="45,2,2,2" FontSize="{DynamicResource MediumFontSize}" TextTrimming="CharacterEllipsis" VerticalAlignment="Center" HorizontalAlignment="Left" />
                                                </Grid>
                                                <DataTemplate.Triggers>
                                                    <DataTrigger Binding="{Binding IconData}" Value="{x:Null}">
                                                        <Setter Property="Margin" TargetName="texto">
                                                            <Setter.Value>
                                                                <Thickness Bottom="2" Top="2" Left="10" Right="2"/> 
                                                            </Setter.Value>
                                                        </Setter>
                                                    </DataTrigger>
                                                    <Trigger Property="IsMouseOver" Value="true">
                                                        <Setter Property="Fill" TargetName="icon">
                                                            <Setter.Value>
                                                                <SolidColorBrush Color="#f2f2f2" />
                                                            </Setter.Value>
                                                        </Setter>
                                                    </Trigger>

                                                </DataTemplate.Triggers>
                                            </DataTemplate>
                                        </ListBox.ItemTemplate>
                                    </ListBox>
                                </Border>
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
         </Setter>
    </Style>

Eu quero que no avento de mouse Over do listBox, eu consiga setar o valor de uma propriedade do ModernVerticalMenu...

Alguma idéia de como fazer isso?