I'm pretty sure you can probably do as you want at present, though I can't give examples without a clearer description.

Here's some default output from ^siblings^ (I've added line breaks) from sibling note 'ant':
<ul>
 <li>ant</li>
 <li><a href="bee.html">bee</a></li>
 <li><a href="cow.html">cow</a></li>
 <li><a href="dog.html">dog</a></li>
</ul>

In default web browser styling, the first item will look different as there is no <a> link element but that's not difficult to fix via CSS if all items should look the same.

Quote:

Er, not so. TB applies no specific  styling, i.e. CSS markup, other than that you define in your export code. So, we might use:

^siblings("<ul id="siblist">","<li>","</li>","</ul>")^

Now we get
<ul id="siblist">
 <li>ant</li>
 <li><a href="bee.html">bee</a></li>
 <li><a href="cow.html">cow</a></li>
 <li><a href="dog.html">dog</a></li>
</ul>

Basicalyin your list, every sibling is lists as $Name in an <li> and all except the current note have the $Name enclosed in a link.If you want extra styling hooks you could putl a <p></p> inside the , e.g. a second input of "<li><p>" instead of "<li>", etc.

In your CSS file:

#siblist { /* style the <ul> */ }
#siblist li { /* all <li> in siblist */ }
#siblist li a { /* all <a> in <li> in siblist */ }

You don't need to set an ID but it certainly makes it easier to style this <ul> differently from others on the page.

However, I'm not clear how/where the proposed sib-prefix and sib-sufix are used.

As I understand it, the optional fifth linkType filter argument only applies to ^inboundTextLinks^, ^outboundTextLinks^, ^inboundBasicLinks^, ^outboundBasicLinks^ and ^outboundWebLinks^. As ^siblings^ lists all siblings a linkType filter wouldn't have anything to act on.  In testing (v5.10.1) supplying such an input has no effect on the HTML output.