Moving items down when adding error info using INotifyDataErrorInfo - wpf

Question

I have for example a combobox and if it is not chosen then I am displaying an error message under it.
When the message is displayed it is displayed on top of the control that is under the combobox.
Is there a way to move the control(s) under the combobox down when the error message is shown?
<UserControl.Resources>
<Style x:Key="ErrorStackPanel" TargetType="{x:Type StackPanel}">
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter Property="Margin" Value="0 20 0 5"/>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="ErrorComboBox" TargetType="{x:Type ComboBox}">
<Setter Property="MinWidth" Value="180" />
<Setter Property="Validation.ErrorTemplate">
<Setter.Value>
<ControlTemplate>
<StackPanel Orientation="Vertical" SnapsToDevicePixels="True">
<!--Placeholder for the TextBox itself-->
<AdornedElementPlaceholder x:Name="textBox" />
<ItemsControl ItemsSource="{Binding}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding ErrorContent}"
Foreground="Maroon"
FontWeight="Bold"
Margin="5 2 0 0"
/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</UserControl.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="auto" />
<RowDefinition Height="auto" />
</Grid.RowDefinitions>
<StackPanel Grid.Row="2" Margin="10 5">
<Label Content="Switch" />
<ComboBox Style="{StaticResource ErrorComboBox}" ItemsSource="{Binding Switches}" SelectedItem="{Binding SelectedSwitch}"
DisplayMemberPath="Name" HorizontalAlignment="Left">
</ComboBox>
</StackPanel>
<StackPanel Grid.Row="3" Margin="10 10" Style="{StaticResource ErrorStackPanel}">
<RadioButton GroupName="pres"
IsChecked="{Binding TriggerOnPress}"
Content="On" Margin="0 5" />
<RadioButton GroupName="pres"
IsChecked="{Binding TriggerOnPress, Converter={valueconverters:BoolInverterConverter}}"
Content="Off" Margin="0 5"/>
</StackPanel>

Answer 1

StackPanel doesn't have error state. Apply trigger to ComboBox and change bottom margin:
<Style x:Key="ErrorComboBox" TargetType="{x:Type ComboBox}">
<Setter Property="MinWidth" Value="180" />
<Setter Property="Validation.ErrorTemplate">
<Setter.Value>
<ControlTemplate>
...
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter Property="Margin" Value="0 0 0 20"/>
</Trigger>
</Style.Triggers>
</Style>