Concept is to stash entry_ids of playa entries to pass to jquery-nivoslider call, so that both the slider div and the call will not have identical slider ID's resulting with conflict.

{exp:stash:set_list 
name="rehab_list" 
parse_tags="yes" 
trim="yes" 
parse_depth="4"
}

   {exp:channel:entries 
   channel="rehab" 
   url_title="{segment_3}" 
   limit="1"
   require_entry="yes"
    }

    {stash:rehab_entry_id}{entry_id}{/stash:rehab_entry_id}
    {stash:rehab_url_title}{url_title}{/stash:rehab_url_title}
    {stash:rehab_title}{title}{/stash:rehab_title}

{stash:playa_stash_test}test{/stash:playa_stash_test}

   {exp:stash:set_list:nested   
name="rehab_update_list"      
trim="yes"
parse_tags="yes" 
parse_depth="3"   
} 

    {exp:playa:parents 
    channel="rehab_update" 
   
    limit="10"}
    
          {stash:playa_test}test22{/stash:playa_test}
               0{stash:playa_entry}|{entry_id}{/stash:playa_entry}
                {stash:playa_title|{title}{/stash:playa_title}
   
                {image_uploads sort="asc"}{photo_images size="thumbnail"}     
                {stash:playa_entry_img}{photo:url}{/stash:playa_entry_img}
                {stash:playa_entry_img_label}photo_label}   {/stash:playa_entry_img_label}
        {/photo_images} {/image_uploads}

   {stash:playa_summary_update}{summary_update}{/stash:playa_summary_update}
   {stash:playa_materials_needed}{materials_needed}{/stash:playa_materials_needed}
   {stash:playa_steps_taken}{steps_taken}{/stash:playa_steps_taken}

    {/exp:playa:parents}
     {/exp:stash:set_list:nested}
  {/exp:channel:entries}
  {/exp:stash:set_list}