There is nothing out of the box that will let you send an email to multiple email address for one account, but you can hook a function to wp_mail
filter and check based on to address or subject line and add your cc/bbc to that filter, ex:
// Add extra contact info fields to user profile page
function extra_contact_info_wpa_134454($contactmethods) {
$contactmethods['bcc'] = 'Email BCC';
$contactmethods['cc'] = 'Email CC';
return $contactmethods;
}
add_filter('user_contactmethods', 'extra_contact_info_wpa_134454');
add_filter('wp_mail','add_cc_bcc_to_mail_wpa_134454');
function add_cc_bcc_to_mail_wpa_134454($args){
//try to get the user id by the "to mail"
$user = get_user_by( 'email', $args['to'] );
if ($user){
//get ccs if exists
if ( ($cc = get_user_meta( $user->ID, 'cc', true ) ){
//explode by comma "," to allow multiple cc addresses
foreach ((array)explode(",", $cc) as $email) {
$args['headers'][] = 'Cc: '.$email;
}
}
if ( ($bcc = get_user_meta( $user->ID, 'bcc', true ) ){
//explode by comma "," to allow multiple bcc addresses
foreach ((array)explode(",", $bcc) as $email) {
$args['headers'][] = 'Bcc: '.$email;
}
}
}
return $args;
}
Now on every mail send it will check if the mail belongs to a user and if it does it will check if that user has entered cc or bcc email addresses in his profile which will be added to that mail.