getting the Matrix rows of a Playa entry

Question

I have the following Stash variable list to get the related author of an article

{exp:stash:set_list name="my_list" parse_tags="yes" parse_depth="2"}
    {exp:playa:children var_prefix="children" entry_id="{entry_id}"}

        {stash:author_name}{children:title}{/stash:author_name}
        {stash:author_bio}{children:profile_bio}{/stash:author_bio}
        {stash:item_entry_id}{children:entry_id}{/stash:item_entry_id}

    {exp:stash:set_list:nested name="related_entries" context="{children:entry_id}" parse_tags="yes"}
        {!-- Matrix tag pair --}
        {profile_social_media}
            {stash:related_title}{url}{/stash:related_title}
        {/profile_social_media}
    {/exp:stash:set_list:nested}

    {/exp:playa:children}
{/exp:stash:set_list}

but struggling to then get the social media profiles contained within a Matrix field for that related author.

Then in the wrapper we have

 {exp:stash:get_list name="my_list"}
    <div class="{switch='row|rowAlt'}">
        <h1>{author_name} (item {count} of {absolute_results})</h1>

    {author_bio}

    {exp:stash:get_list:nested name="related_entries" context="{item_entry_id}" prefix="nested"}
            <div class="{nested:switch='row|rowAlt'}">
                {related_title} (Related item {nested:count} of {nested:absolute_results})
            </div>
        {/exp:stash:get_list:nested}

    </div>
{/exp:stash:get_list}

Author name and bio are fine, just not the Matrix rows.

Answer 1

So my Stash logic here was correct in so much that it was setting the var correctly, but the var_prefix was where the setting of the var was failing.

So the set_list:nested should have been like:

{exp:stash:set_list:nested name="related_entries" context="{children:entry_id}" parse_tags="yes"}
  {!-- Matrix tag pair --}
  {children:profile_social_media}
    {stash:related_title}{children:url}{/stash:related_title}
  {/children:profile_social_media}
{/exp:stash:set_list:nested}