Позиционирование встроенных блоков DIV внутри контейнера DIV (без flexbox)

.parent {
  border: 1px solid red;
  height: 150px;
  width: 100%;
  display: table;
}

.parent > * {
  display: table-cell;
    text-align: center;
    vertical-align:middle;
}

#div1,
#div2 {
  display: inline-block;
  border: 1px solid blue;
}

<div class = "parent">
  <div>
    <div id = "div1">
      <span>Lorem ipsum dolor sit, amet consectetur adipisicing elit. 
     </span>
    </div>
    <div id = "div2">
      <span>Lorem ipsum dolor sit amet, consectetur adipisicing elit. 
     </span>
    </div>
  </div>
</div>