Changing content of one label, based on the content of another

Question

Hello all,
I need some advice on how to go about doing something that should be simple.
Basically, I have two labels, that will be used in a marquee animation. When label one gets changed, I want label two to mimic label one's content. Since there is no ContentChanged Event for labels, I have been relying on the SizeChanged event of label one
to do the job.
However, the issue arises when label one's content extends past that of its parent container, thus no longer firing SizeChanged.
When label one's supposed length is equal to or greater than that of its container, is when I would start the marquee animation.
Basically, I need a sure fire, reliable, 100% accurate way to update label two's content to match that of label one's despite its length.
I have read the following: Label.Content Changed Event
However this does not solve the issue, as the event fires for "all" custom label classes, due to the ContentProperty being declared Static/Shared.
Thanks in advance!

Answer 1

<UserControl x:Class="CustomControls.UserControls.ValidationUserControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d" Height="36" Width="120">
<Grid x:Name="z">
<TextBox x:Name="txtBase" Text="TextBox" Margin="0,0,0,13"/>
<Label x:Name="lblStatus" Content="Status" HorizontalAlignment="Left" Margin="5,0,0,0" VerticalAlignment="Bottom" FontSize="10" Foreground="#FFE12828" FontWeight="Bold">
<Label.Effect>
<DropShadowEffect BlurRadius="5" ShadowDepth="1"/>
</Label.Effect>
</Label>
<Label x:FieldModifier="Friend" x:Name="lblMarquee" Content="{Binding ElementName=lblStatus, Path=Content}" HorizontalAlignment="Right" Margin="0,23,-29,0" FontSize="10" Foreground="#FFE12828" FontWeight="Bold" Background="Transparent" Height="13" VerticalAlignment="Top">
<Label.Effect>
<DropShadowEffect BlurRadius="5" ShadowDepth="1"/>
</Label.Effect>
</Label>
</Grid>
</UserControl>