storyboard target not clear - xaml

Question

Why the storyboard is fading my TextBox x:Name="WelcomeText" inside RelativePanel x:Name="WelcomeRelativePanelUserControl".
In my comprehension the storyboard target is
the FlipView x:Name="fvWelcome" inside the RelativePanel x:Name="fvWelcomeRelativePanel"
<RelativePanel x:Name="WelcomeRelativePanelUserControl" Background="#FF1F4E79" >
<TextBox x:Name="WelcomeText"
RelativePanel.AlignLeftWithPanel="True"
Margin="145,0,0,0"
Foreground="White"
FontFamily="Segoe UI"
IsReadOnly="True"
BorderBrush="#FF1F4E79"
BorderThickness="0"
HorizontalAlignment="Center"
FontSize="84"
TextWrapping="Wrap"
AcceptsReturn="True"
Background="#FF1F4E79"
Text="Welcome"/>
</RelativePanel>
The other control:
<RelativePanel x:Name="fvWelcomeRelativePanel">
<FlipView x:Name="fvWelcome"
RelativePanel.AlignBottomWithPanel="True">
<FlipView.Triggers>
<EventTrigger>
<BeginStoryboard>
<Storyboard x:Name="FlpVOpacity">
<DoubleAnimation
Storyboard.TargetName="fvWelcome"
Storyboard.TargetProperty="(FlipView.Opacity)"
AutoReverse="True"
From="0"
To="1"
Duration="0:0:4"
RepeatBehavior="1x"/>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</FlipView.Triggers>
<FlipView.ItemTemplate >
<DataTemplate>
<Grid>
<Grid.RowDefinitions>
<RowDefinition x:Name="Welcome" Height="0.3*"/>
<RowDefinition x:Name="GuestName" />
</Grid.RowDefinitions>
<TextBox x:Name="GuestNameTextBox"
Grid.Row="1"
IsReadOnly="True"
Foreground="White"
Margin="145,0,0,0"
FontFamily="Segoe UI"
BorderBrush="#FF1F4E79"
BorderThickness="0"
Text="{Binding}"
FontSize="84"
TextWrapping="Wrap"
AcceptsReturn="True"
Background="#FF1F4E79">
</TextBox>
</Grid>
</DataTemplate>
</FlipView.ItemTemplate>
</FlipView>
</RelativePanel>
My fade effect is working well but why does the text of my TextBox x:Name="WelcomeText" also fade? It shouldn't. I don't understand why? And how can I forbid this effect on this textbox and make it run on the TextBox x:Name="GuestNameTextBox" in the second control fvWelcome

Answer 1

<RelativePanel x:Name="GeneralPanelGuest">
I resolved it just by putting this general relativePanel with 2 others RelativePanel for each of the 2 differents items that I didn't want to have the same behavior and by removing the grid inside the fliepView that I used to put the welcome above which was making inheritance
<RelativePanel x:Name="WelcomeRelativePanelUserControl" Background="#FF1F4E79" >
<TextBox x:Name="WelcomeText"
RelativePanel.AlignLeftWithPanel="True"
Margin="145,0,0,0"
Foreground="White"
FontFamily="Segoe UI"
IsReadOnly="True"
BorderBrush="#FF1F4E79"
BorderThickness="0"
HorizontalAlignment="Center" FontSize="84"
TextWrapping="Wrap" AcceptsReturn="True"
Background="#FF1F4E79"
Text="Welcome"
/>
<TextBlock x:Name="WelcomeTextException2"
RelativePanel.AlignLeftWithPanel="True"
RelativePanel.Below="WelcomeText"
Margin="215,0,0,0"
Foreground="White"
FontFamily="Segoe UI"
HorizontalAlignment="Center" FontSize="34"
/>
</RelativePanel>
<RelativePanel x:Name="relFvWelcome" RelativePanel.Below="WelcomeRelativePanelUserControl">
<FlipView x:Name="fvWelcome"
VerticalAlignment="Center"
Background="#FF1F4E79"
RelativePanel.AlignBottomWithPanel="True"
>
<FlipView.Triggers>
<EventTrigger>
<BeginStoryboard>
<Storyboard x:Name="FlpVOpacity">
<DoubleAnimation
Storyboard.TargetName="fvWelcome"
Storyboard.TargetProperty="(FlipView.Opacity)"
AutoReverse="True"
From="0" To="1" Duration="0:0:4"
RepeatBehavior="1x"
/>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</FlipView.Triggers>
<FlipView.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Vertical"/>
</ItemsPanelTemplate>
</FlipView.ItemsPanel>
<FlipView.ItemTemplate >
<DataTemplate>
<TextBox x:Name="GuestNameTextBox"
Grid.Row="1"
IsReadOnly="True"
Foreground="White"
Margin="145,0,0,0"
FontFamily="Segoe UI"
BorderBrush="#FF1F4E79"
BorderThickness="0" Text="{Binding}"
FontSize="84"
TextWrapping="Wrap" AcceptsReturn="True"
Background="#FF1F4E79"
>
</TextBox>
</DataTemplate>
</FlipView.ItemTemplate>
</FlipView>
</RelativePanel>
</RelativePanel>