Linda, you can create a constructed list that uses the INSERT function to assist here.
Let's say I have a parent list called ItemsList and it contains 10 items. Also assume item 7 is the control item that you would like to insert in to position 5.
Try this ...
Constructed lists are evaluated in a sequential order from top to bottom. Looking at this constructed list, we are adding in items 1-6 and 8-10, then randomising them, then inserting item 7 in to position 5.
Hope that gets your problem solved.