How to spawn objects relative to parent coordinates?

Hello everyone! I created a empty object (parent). I`m trying to spawn platforms in this parent and ROTATING the parent. Spawn and rotating occur in turn. But platforms don`t spawn where they should! Objects spawn in the right place if i won`t rotate the parent. So, I tried to implement it in these ways: 1. _position = platform.transform.localPosition; // In the Unity scene the platform is already IN parent (it takes parents coordinates) Instantiate ( platform, _position, Quaternion.identity, parent.transform ); 2. GameObject helper = Instantiate ( platform, _position, Quaternion.identity); helper.transform.parent = parent.transform; It isn`t working... i think the problem is in the topic of my question but i don`t know what to do...