Grid field inside of Relationship field = random result?

Hi! Hoping for insight.

Perhaps something changed recently that has caused my Grid fields inside of a Relationship entries not to display. I am on EEv5.3.0 and nothing has changed in my code/content to cause this issue (that I know off…). Here is a simplified snippet of my code with the issue commented:

{exp:channel:entries channel="channel_with_relationship_field"}

  {relationship_field}

    {relationship_field:title} // The title renders fine from the relationship entry as well as other fields...

    {if relationship_field:grid_field} // ...except grid fields. Not even recognized

    {relationship_field:grid_field} // Sometimes, it will find a Grid field even if the entry doesn't actually have one!

      {grid_field:grid_field_label} // It's a rare thing if this gets rendered.

    {/relationship_field:grid_field}

    {/if}

  {/relationship_field}

{/exp:channel:entries}

More info: The channel entries that is being pulled by Relationship field has 3 Grid fields. Out of 10 entries, only 3 use those Grid fields. These are the purposes of those Grid fields:

• Show image with a link to a file or URL
• Show a button with a link to file or URL
• Show a list of links to file or URL

I have tried the following approaches:

• Simplified the code on a test page.
• I reordered the Relationship entries. No change.
• I printed the entry_id for the Relationship entries and they all check out.
• I created a new Relationship field and populated it with the same entries that have the Grid fields. Still not finding the Grid fields
• I created one new Grid field (without deleting old ones) and it found the Grid and rendered its stuff.
• I created additional Grid fields to mimic the other 3 fields and none of them rendered.

I am not sure what to try now. If the functionality changed, then is there another approach to render a list of channel entries on a page that have a sub-listing of things to render? Maybe Fluid field?

Thank you in advance, -Reid