class A extends ParentA {
    public function someFn1() { $a = 1 + 3; echo $a; parent::someFn1() }
    public function someFn2() { $b = rand(10); echo $b; parent::someFn2() }
}

class B extends ParentB {
    public function someFn1() { $a = 1 + 3; echo $a; parent::someFn1() }
    public function someFn2() { $b = rand(10); echo $b; parent::someFn2() }
}

class C extends ParentC {
    public function someFn1() { $a = 1 + 3; echo $a; parent::someFn1() }
    public function someFn2() { $b = rand(10); echo $b; parent::someFn2() }
}

class D extends ParentD {
    public function someFn1() { $a = 1 + 3; echo $a; parent::someFn1() }
    public function someFn2() { $b = rand(10); echo $b; parent::someFn2() }
}

class Parent {
    abstract public function someFn1();
    abstract public function someFn2();
}

class ParentA {
    public function someFn1() { echo "ParentA fn1" };
    public function someFn2() { echo "ParentA fn2" };
}

class SomeName extends ParentA {
    public function someFn1() { ... };
    public function someFn2() { ... };
}

trait someFunctions {
    public static function someFn1() { $a = 1 + 3; echo $a; parent::someFn1(); }
    public static function someFn2() { $b = rand(10); echo $b; parent::someFn2(); }
}

class A extends ParentA {
    use someFunctions;
}

class B extends ParentB {
    use someFunctions;
}

class C extends ParentC {
    use someFunctions;
}

class D extends ParentD {
    use someFunctions;
}