php how to check if date string in between dates : <p>I have date in string. i.e: 18/10/2018</p>

<p>and also date in an object: $pnrProduct['Date'] . i.e 20/10/2018</p>

<p>I would like to check if the second date is bigger then the first one (in this case it is bigger)</p>

<p>how can i do that?</p>
