Switch off WPTouch plugin for the Spirit theme

I've just create a child theme of Spirit. I have added code that filters out the plugin WPTouch. Wordpress complains "Broken Theme: The "uf-spirit" theme is not a valid parent theme." I understand now that Spirit is already child theme. I want to use Spirit but I want to switch off WPTouch for Spirit in a way that won't get sat on when I upgrade Spirit (or any other standard components).

How do I do this?