Childwindow javascript method opening another child window

Question

I am opening a child window using window.showModalDialog(). In child window I am calling another javascript method OK button click. When I do "OK Button" click in child window, another new child window is opening un-wantedly. Please follow my steps

1. Here is the Parent Javascript method with window.showModalDialog() 2.In ProfilePic.aspx in OK button click I am calling Javascript method.
   1. When call CallParentScript() is It is opening another child window. I dont understand whey it is happening.
   2. It is happening Cancel button too in child window.

How to solve this? I need to pass return value to parent window when I close child window.

Note: new child window opening in child window before alert(weburl); call. Update 10:45AM: I just debug my code. new window is opening before 1st statement in "btnOK_Click" and executing all statements in codebehind.