使用CSS，有没有一种方法可以让多个DIV重叠在一个兄弟DIV上？

<style>
  .parent {
    position: relative;
    width: 200px;
    height: 200px;
    background-color: #e0e0e0;
  }

  .sibling {
    position: absolute;
    top: 50px;
    left: 50px;
    width: 100px;
    height: 100px;
    background-color: red;
    z-index: 1;
  }

  .overlapping-div {
    position: absolute;
    top: 75px;
    left: 75px;
    width: 100px;
    height: 100px;
    background-color: blue;
    z-index: 2;
  }
</style>

<div class="parent">
  <div class="sibling"></div>
  <div class="overlapping-div"></div>
</div>