How to remove element from collection at child control level - wpf

Question

I've created UserControl for adding/removing attributes using the buttons. It has ItemsControl with ObservableCollection of attributes bound to it as a ViewModel and button for adding new attribute to collection. Each new attribute creates an entity in collection which is also a UserControl with bound attribute ViewModel and button for deleting itself.
I wanted to write this functionality so the single attribute control (and other controls) can be reusable - and I use it in a few places. Currently adding new attributes works properly, but I can't find any working way for delete button to work properly and remove object from the collection.
I tried to refer through this.Parent, but CustomAttributeControl's parent is null, I tried to refer through Tag or use Prism.Core, but I couldn't implement anything properly for this to work and I couldn't find anyone with similar nested controls problem to base on. It's easy when there is no nested control for single attribute, but here I can't come up with anything. I'm fairly new to WPF and I feel there should be an easy way to do this.
single attribute control
attribute control's XAML:
<UserControl x:Class="xxx.UI.CustomAttributeControl"
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"
xmlns:models="clr-namespace:xxx.ViewModels.Attributes"
mc:Ignorable="d" >
<DockPanel Width="auto" HorizontalAlignment="Stretch" Margin="0,2">
<TextBox Text="{Binding Name}" Height="20" TextWrapping="Wrap" Width="160"/>
<TextBlock Width="60"/>
<ComboBox x:Name="DataType" Height="20" Width="120" SelectionChanged="DataType_SelectionChanged"/>
<TextBlock Width="10"/>
<TextBox Text="{Binding ListValues}" x:Name="ListValues" Height="20" TextWrapping="Wrap" Width="120"/>
<DockPanel HorizontalAlignment="Right">
<CheckBox IsChecked="{Binding Visible}" VerticalAlignment="Center" HorizontalAlignment="Right" Margin="20,0"/>
<Button x:Name="Delete" Content="X" Width="22" Height="20" VerticalAlignment="Center" HorizontalAlignment="Right" Margin="20,0"/>
</DockPanel>
</DockPanel>
</UserControl>
list control
list control's XAML:
<UserControl x:Class="xxx.UI.CustomAttributesControl"
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"
xmlns:local="clr-namespace:xxx.UI"
mc:Ignorable="d">
<StackPanel>
<Label FontSize="20">Custom attributes</Label>
<StackPanel>
<DockPanel HorizontalAlignment="Stretch">
<Label Width="160" HorizontalAlignment="Left" HorizontalContentAlignment="Center">Attribute name</Label>
<TextBlock Width="60"/>
<Label Width="120" HorizontalAlignment="Left" HorizontalContentAlignment="Center">Attribute type</Label>
<TextBlock Width="10"/>
<Label Width="120" HorizontalAlignment="Left" HorizontalContentAlignment="Center">List values</Label>
<DockPanel HorizontalAlignment="Right">
<Label Width="60" HorizontalAlignment="Right" HorizontalContentAlignment="Center">Visible</Label>
<Label Width="60" HorizontalAlignment="Right" HorizontalContentAlignment="Center">Delete</Label>
</DockPanel>
</DockPanel>
<ItemsControl ItemsSource="{Binding}"> <!-- it's binding ObservableCollection of custom attributes from parent control -->
<ItemsControl.ItemTemplate>
<DataTemplate>
<local:CustomAttributeControl />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<DockPanel HorizontalAlignment="Right">
<Button Margin="20,10" Click="AddAttribute">+ Add attribute</Button>
</DockPanel>
</StackPanel>
</StackPanel>
</UserControl>
Code for adding attribute in .xaml.cs:
private void AddAttribute(object sender, RoutedEventArgs e)
{
var attributes = (ObservableCollection<CustomAttribute>)DataContext;
attributes.Add(new CustomAttribute());
}