How to find the child element of WPF DockingManager?

<syncfusion:DockingManager x:Name="SyncDockingManager" DockFill="True" UseDocumentContainer="True">
  <ContentControl Name="Content1" syncfusion:DockingManager.Header="Tab1" syncfusion:DockingManager.State="Document"/>
  <ContentControl Name="Content2" syncfusion:DockingManager.Header="Tab2" syncfusion:DockingManager.State="Document"/>
  <ContentControl Name="Content3" syncfusion:DockingManager.Header="Tab3" syncfusion:DockingManager.State="Document"/>
  <ContentControl Name="Content4" syncfusion:DockingManager.Header="Tab4" syncfusion:DockingManager.State="Document"/>
</syncfusion:DockingManager>        
<Button x:Name="button" Content="clickhere" Click="button_Click" VerticalAlignment="Bottom" HorizontalAlignment="Right"/>

public partial class MainWindow : Window
{
  public MainWindow()
  {
    InitializeComponent();            
  }
 
  internal FrameworkElement FindChild(string nameForFind)
  {
    foreach (FrameworkElement element in SyncDockingManager.Children)
    {
      if (nameForFind == element.Name)
      {
        return element;
      }
    }
    return null;
  }
 
  private void button_Click(object sender, RoutedEventArgs e)
  {
    if (SyncDockingManager != null)
    {
      FrameworkElement Name = FindChild("Content2");
      if(Name == null)
      {
        MessageBox.Show("Child doesn't exsits in this name");
      }
               
      else
      {
        MessageBox.Show("Header of the element is " + DockingManager.GetHeader(Name));
      }
    }    
  }
}