Hi famarinu,
Making the same structure on child theme will not overwrite the parent theme. What you need to do is first unhook the functions and then only customize the code. We have replied many time on how to unhook the functions. View example below which is just an example.
// Unhook default Thematic functions
function unhook_thematic_functions() {
// Don't forget the position number if the original function has one
add_action( 'attitude_header', 'attitude_headercontent_details', 10 );
}
add_action('init','unhook_thematic_functions'); // removes the header content by using hook attitude_header
add_action( 'attitude_headercontent_details', 'attitude_child_headercontent_details', 10 );
funtion attitude_child_headercontent_details(){
// your stuff
}
Thank you!