VBA dynamic checkbox to show/hide dynamic textbox

I have been searching for an answer to this for days, so I apologise if this has already been answered, but I cannot find it!!

I have a userform in Excel. It takes the user through a number of stages, starting with over 170 email accounts of which they may have access. Once they have selected the ones they use, a list in a second frame on a second tab of a multipage shows this (now smaller) list asking them to tick those they need to use to contact with external suppliers, etc.

I have all of these checkboxes created dynamically for both the list and when the second list of checkboxes is created, a corresponding textbox is created and hidden.

There is no way of telling if a user will select 1 or all of the email accounts and which ones they would be. I have all of the checkboxes in the second list named "MB_External" and then a number starting at 1. The corresponding textboxes are named "MB_Email" and then the same number as the MB_External.

I need the textbox that corresponds to the checkbox to be visible is the check box is true and hidden if false.

As they are all dynamic and not in a structured number pattern, I need to use a Class Module, but I cannot seem to find anything that works or comes close to answering the problem. Everything I have found so far seems to assume you know how many checkboxes are in the frame to start with.

For you info, the frame being used is Frame4 and all of my declarations are public in a separate module. Any help would be greatly appreciated.