Adding javascript file to responsive child-theme

I am trying to create a dropdown menu with multiple drop down fields using this for tablet: http://osvaldas.info/drop-down-navigation-responsive-and-touch-friendly

I found this in a forum post 8 months ago:
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Create a functions.php in your Child Theme and see this paste please http://pastebin.com/iUynbySg

Emil
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But when I tried that I get an error that two header are trying to be called and that the update cannot be made.

My site is wmis.logica3.com