This code will put any volunteer with an image on the current page:

<p> Recent Supporters </p>
{% for signup in site.recent_supporters_with_pictures limit:18 %}
{% if signup.is_volunteer %}
{{ signup.profile_image }}

{% endif %}
{% endfor %}

</div>
{% endif %}

• If most of your volunteers don't have images, you may want to display their names instead of the images  
• If your volunteers aren't in the most recent 18 signups, they won't show on the page.

One way to find out if your recent volunteers have images is to run an advanced search for volunteers who have joined in the last week. The results will show you the recent volunteers. A scan of the page will show which ones have images that will show on the page.