Edit in JSFiddle

* {
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
}

body {
    padding: 1em;
}

.parent {
    width: 49%;
    float: right;
    height: 10em;
    background: deepskyblue;
    padding: 1em;
    font-family: Helvetica, Arial, sans-serif;
}

.parent.position {
    float: left;
}

.position {
    position: relative;
}

.child {
    position: absolute;
    top: 0;
    right: 0;
    
    width: 1em;
    height: 1em;
    padding: .25em;
    background: tomato;

    text-align: center;
    font-size: 2em;
    line-height: .5em;
    color: black;
    text-decoration: none;
}

<div class="parent position"> <strong>Relative</strong> parent
    <a href="#" class="child">&times;</a>
</div>

<div class="parent"> <strong>Static</strong> parent
    <a href="#" class="child">&times;</a>
</div>