Adding layout template to child theme

I am trying to change the template of my posts on a child theme. I understand I have to use remove_action to stop the other filter from pulling in the templates before adding my own. This code is where I am getting stuck.

Could you help me correct this code?

Currently I have….

<?php 

	// Unhook default Responsive functions
function unhook_responsive_functions() {
    // we put the position number of the original function (5)
    // for priority reasons
    remove_action( 'responsive_theme_options', 'responsive_valid_layouts',5);
}
add_action( 'init', 'unhook_responsive_functions' );

	?>