Get Parent Theme Author Name

Thanks for all the help which pointed me in the right direction. In the end I used the following:

$style_parent_theme = wp_get_theme(get_template());
$style_parent_theme_author = $style_parent_theme->get( 'Author' );

I use get_template() to recover the folder name of the parent theme.

wp_get_theme then get’s the theme object.

Once we have that we can manipulate the object to get the author name.