inheritance.php

class Ancestor
{
    private static test()
    {
        echo "Ancestor::test";
    }
    
    public static proxy()
    {
        self::test();
    }
}

class Offspring extends Ancestor
{
    private static test()
    {
        echo "Offspring::test";
    }
}

Offspring::proxy();

<?php
    class Ancestor
    {
        private function test()
        {
            echo "Ancestor::test";
        }

        public function proxy()
        {
            $this->test();
        }
    }

    class Offspring extends Ancestor
    {
        private function test()
        {
            echo "Offspring::test";
        }
    }

    $of = new Offspring();
    $of->proxy();