Can I add ‘Ask to Buy’ for an adult member in my family in family sharing for Apple?

We have had family sharing turned on for a while and it’s been pretty great with one niggle. One member of the family has an issue with being an impulse buyer and the charges are starting to add up. I know how to configure ‘Ask to Buy’ for kids but can’t seem to find something similar for an adult member of the family.

I basically want to add a speed bump to this person’s purchases and was hoping that there is a solution out there. Would appreciate any help I can get on this. Cheers!