Hi @redwire
I’m afraid it’s not possible. But if you can create a query with parameters that can return the post parent and its children based on the search parameter, I believe you can use “acf/fields/relationship/query” hook to do it. This page should give you more idea about it: http://www.advancedcustomfields.com/resources/acf-fields-relationship-query/.
I hope this makes sense.