[SOLVED] How to set z index Urho 2d

I Have few static sprite setup like

Sprite2D* bks = cache->GetResource<Sprite2D>("Urho2D/robot_shuttel.jpg"); SharedPtr<Node> bksn(scene_->CreateChild("bk")); StaticSprite2D* bkss = bksn->CreateComponent<StaticSprite2D>(); // bkss->SetBlendMode(BLEND_ALPHA); // bksn->SetPosition(Vector3(0.0, 0.0, 1)); bkss->SetSprite(bks);

and also few animated.

some how z index in not as per order of creation. Any particular way to set z-index

works. Thanks