diff --git a/src/Dock.Avalonia.Themes.Fluent/Controls/ProportionalDockControl.axaml b/src/Dock.Avalonia.Themes.Fluent/Controls/ProportionalDockControl.axaml
index b947489a1..a2bf1471c 100644
--- a/src/Dock.Avalonia.Themes.Fluent/Controls/ProportionalDockControl.axaml
+++ b/src/Dock.Avalonia.Themes.Fluent/Controls/ProportionalDockControl.axaml
@@ -24,8 +24,10 @@
                         Classes="ProportionalStackPanel">
             <ItemsControl.Styles>
               <Style Selector="ItemsControl.ProportionalStackPanel > ContentPresenter">
+                <Setter Property="(ProportionalStackPanel.Proportion)"
+                  Value="{Binding Proportion, Mode=TwoWay}" />
                 <Setter Property="(ProportionalStackPanel.CollapsedProportion)"
-                        Value="{Binding CollapsedProportion}" />
+                  Value="{Binding CollapsedProportion, Mode=TwoWay}" />
                 <Setter Property="(ProportionalStackPanel.IsCollapsed)">
                   <Setter.Value>
                     <MultiBinding Converter="{x:Static BoolConverters.And}">
diff --git a/src/Dock.Avalonia/Controls/ProportionalDockControl.axaml.cs b/src/Dock.Avalonia/Controls/ProportionalDockControl.axaml.cs
index 8252f9af6..78e38d953 100644
--- a/src/Dock.Avalonia/Controls/ProportionalDockControl.axaml.cs
+++ b/src/Dock.Avalonia/Controls/ProportionalDockControl.axaml.cs
@@ -4,9 +4,6 @@
 using Avalonia.Controls;
 using Avalonia.Controls.Metadata;
 using Avalonia.Controls.Primitives;
-using Avalonia.Data;
-using Dock.Controls.ProportionalStackPanel;
-using Dock.Model.Core;
 
 namespace Dock.Avalonia.Controls;
 
@@ -16,34 +13,4 @@ namespace Dock.Avalonia.Controls;
 [TemplatePart("PART_ItemsControl", typeof(ItemsControl), IsRequired = true)]
 public class ProportionalDockControl : TemplatedControl
 {
-    private ItemsControl? _itemsControl;
-
-    /// <inheritdoc /> 
-    protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
-    {
-        // Unsubscribe from the previous ItemsControl if it exists
-        if (_itemsControl != null)
-        {
-            _itemsControl.ContainerPrepared -= ItemsControlOnContainerPrepared;
-            _itemsControl = null;
-        }
-
-        base.OnApplyTemplate(e);
-
-        var itemsControl = e.NameScope.Find<ItemsControl>("PART_ItemsControl");
-
-        if (itemsControl != null)
-        {
-            _itemsControl = itemsControl;
-            _itemsControl.ContainerPrepared += ItemsControlOnContainerPrepared;
-        }
-    }
-
-    private void ItemsControlOnContainerPrepared(object? sender, ContainerPreparedEventArgs e)
-    {
-        if (e.Container.DataContext is IDockable)
-        {
-            e.Container[!ProportionalStackPanel.ProportionProperty] = new Binding(nameof(IDockable.Proportion));
-        }
-    }
 }