how to copy all mail to titi@toto.org to toto@free.fr with postfix

Hello,
I've postfix, mysql,maildrop, courier-imap installed with multi domains
like toto.org.

I'd like that all mails send to titi@toto.org, be copied to titi@free.fr

I've this in my main.cf:

virtual_mailbox_domains = mysql:/etc/postfix/mysql-virtual-domains.cf
virtual_alias_maps = mysql:/etc/postfix/mysql-virtual.cf
virtual_mailbox_base = /home/vmail
virtual_mailbox_maps = mysql:/etc/postfix/mysql-virtual-maps.cf

In mysql-virtual-maps.cf, I've this
user = vmail
password = tbjb1820
dbname = mail
table = postfix_users
select_field = maildir
where_field = email
additional_conditions = and postfix = 'Y'
hosts = 127.0.0.1

here, I put all my users's mailbox (like titi@toto.org)

In mysql-virtual.cf, I've this

user = vmail
password = tbjb1820
dbname = mail
table = postfix_virtual
select_field = destination
where_field = email
hosts = 127.0.0.1

it's like this in phpmyadmin
email destination
tata@toto.org titi@toto.org

and all mails to tata@toto.org are forwarded to titi@toto.org.

But I can't copy mails for titi@toto.org to titi@free.fr.

If I put that:
email destination
titi@toto.org titi@toto.org
titi@toto.org titi@free.fr

I don't understand why it works but titi@free.fr receives two copies of
the mail...

What do you think of that?

Thanks.

Bye