Register Widget for Theme With No Hooks

// Register After Post Widget - 2013 Child Theme

function wpsites_after_post_widget () {

register_sidebar( array(
'id'	=> 'after-post',
'name'	=> __( 'After Post', 'twentythirteenchild' ),
'description'	=> __( 'This is the after post widget.', 'twentythirteenchild' ),
) );
}

add_action( 'widgets_init', 'wpsites_after_post_widget' );