如何使DataGridCell具有与其第一个子元素相同的边框

<Style TargetType="DataGridCell">
    <Setter Property="BorderThickness" Value="0" />
    <Style.Triggers>
        <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Converter={StaticResource HasFirstChildConverter}}" Value="True">
            <Setter Property="BorderThickness" Value="1" />
            <Setter Property="BorderBrush" Value="Black" />
        </DataTrigger>
    </Style.Triggers>
</Style>

public class HasFirstChildConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value is FrameworkElement element && element is Panel panel)
        {
            return panel.Children.Count > 0;
        }
        return false;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

<DataGrid>
    <DataGrid.Resources>
        <Style TargetType="DataGridCell" BasedOn="{StaticResource {x:Type DataGridCell}}">
            <!-- 定义的样式 -->
        </Style>
    </DataGrid.Resources>
    <!-- DataGrid的其他设置 -->
</DataGrid>