Your words
Code:
parameter pop up box
implies to me an "InputBox" from "[Specify child Name]" in your query, e.g
Code:
SELECT * FROM YourTableOrQueryName WHERE Name = [Specify Child Name]
When the query is run, you'll be prompted to "Specify Child Name" with a textbox to specify the child' name.
My words
implies a control on a form used in a query criteria, e.g.
Forms!YourFormName!ComboBoxName = "Jones, John"
Your query would be
Code:
SELECT * FROM YourTableOrQueryName WHERE Name = Forms!YourFormName!ComboBoxName
When the query is run the forms control's value is put into your query automatically.