How to sort columns in table independently of each other?

I have a table that I am using to store multiple dynamic lists, each in their own column, that are used for a data validation list that depends on the contents of another data validated list cell.

If that isn't clear, search for "contextures create dependent lists using tables" (it won't let me post the link, sorry). That will explain what I'm doing.

I would like to alphabetize each column independently. Doing a sort on the whole table results in blank cells interspersed in the data in some columns, due to each column not having the same number of entries. I do not want to sort the entire rows, only the individual cells in each column.

I understand that columns can be sorted individually when they are not part of a table, but that will not work for me. My data must be in a table in order for it to work as a dependent dynamic list. It took me several frustrating weeks to figure that out.

This seems like such a simple thing to do, but I have not been able to figure out how to do it. Does anyone know how?

If what you're trying to do is to sort the data in a certain column, why not just copy the data in that column to a range then sort it then copy back to the table.