Find element which is in tag selenium

I am trying to find an element which is a arrow (like drop down). But there is no html specific code for that. It seems arrow has been included with <em>. its not visible by default. when I inspect element, I could see it --> [::after ==$0] I could find em element. But not able to locate the arrow. Can anyone help to find this locator? Here is the html code.

<em class="x-btn-split" unselectable="on" id="ext-gn23"><button type="button" id="ext-gn58" class=" x-btn-text"><div class="tbhIcon"></div><span>Relaties</span></button>
::after ==$0
</em>