Custom taxonomy include children

I’m building loops to pull posts based on 2 or more custom taxonomies. Although the plugin includes children of CATEGORIES by default, it only includes children of custom taxonomies with children=true set. Example:
[loop type=academics taxonomy=academic_degree_type term=undergraduate-major children=true taxonomy_2=academic_locations term_2=online compare_2=and list=true orderby=title][field title][/loop]
How do I also set children=true on taxonomy_2. I tried children_2=true, didn’t work.
Thanks, Susan