Accessing a form control inside a group box on the sheet

I have about 100 form control checkboxes on a sheet and have no problem getting to and saving their values. Those are not contained within any group boxes. However, I want to access a specific checkbox that is located inside a group box and that checkbox does not have a meaningful name. I would expect that I could first locate the group, then isolate the checkbox.

How do I loop within a group box, when not on a userform sheet?

I think I have to use .Range(array()) or .Groupitems() but can't seem to make it work.

A way to capture that checkbox (that is located inside a group), while looping through all the checkboxes on mysheet would also be ok since I already do this to save their values.

For Each sh In ws.Shapes If sh.Type = msoFormControl Then If sh.FormControlType = xlGroupBox Then mygroup = sh.name 'need to loop within "mygroup" and find the checkbox Thanks in advance.