Access static variable in non-static method + Inheritance
===

I have the following stucture

    class Foo
    {
        public static $a = "parent";
    
        public static function Load()
        {
            return static::$a;
        }
    
        public function Update()
        {
            return self::$a; 
        }

    }

    class Bar extends Foo
    {
        private static $a = "child";
    }


I want the Update function to be able to return $a aswell, but I can't get it to work.

    Bar::Load();  //returns child, Correct.
    $bar = new Bar();
    $bar->Update(); //returns parent, Wrong.

I've tried self:: , static:: and get_class() without success.