jQuery unwrap removing more than one parent

jQuery unwrap removing more than one parent

I have an html structure like so
<aside class="l-region l-region--sidebar-first">
<div></div>
<div></div>
</aside>
The two divs inside the aside do have classes and child elements but for
the sake of the question you don't need to know what they are. On DOM
ready, I wrap the two inner divs in a new div like so
<aside class="l-region l-region--sidebar-first">
<div class"wrapping-div">
<div class="inner-div-one"></div>
<div class="inner-div-two"></div>
</div>
</aside>
I don't use the wrap() function to get the two divs inside .wrapping-div,
I create that div, append it to the DOM inside the aside and then append
the two inner divs to that new element I created.
When I try to unwrap() those two divs, both .wrapping-div and
.l-region--sidebar-first are removed from the DOM. JS to unwrap the
elements below.
$(function() {
$('.inner-div-one').unwrap();
$('.inner-div-two').unwrap();
});
I thought that unwrap() was supposed to remove one parent. Why is it
removing both and does anyone know how I can stop this?
Cheers.