2 virtual accounts share a folder

Hi,
I have a dedicated server and have 2 websites (lets call the accounts: mydomain and mydoman2) which share images users post on them. The images are stored in:
/home/mydomain/public_html/pics

I would like to have the ability of mydomain2 account to have all rights to read, delete, write from that account.

here is what I have in httpd.conf:
​

<VirtualHost MY_IP_ADDRESS:80>
    ServerName mydomain.com
    ServerAlias www.mydomain.com
    DocumentRoot /home/mydomain/public_html
    ServerAdmin mydomain@mydomain.com
    UseCanonicalName Off
    CustomLog /usr/local/apache/domlogs/mydomain.com combined
    CustomLog /usr/local/apache/domlogs/mydomain.com-bytes_log "%{%s}t %I .\n%{%s}t %O ."
    ## User findhote # Needed for Cpanel::ApacheConf
    UserDir disabled
    UserDir enabled mydomain
     <IfModule mod_suphp.c>
       suPHP_UserGroup mydomain mydomain
    </IfModule>
<IfModule !mod_disable_suexec.c>
SuexecUserGroup mydomain mydomain
</IfModule>
ScriptAlias /cgi-bin/ /home/mydomain/public_html/cgi-bin/


# To customize this VirtualHost use an include file at the following location
# Include "/usr/local/apache/conf/userdata/std/2/mydomain/mydomain.com/*.conf"

Code (markup):

Can you show me how to accomplish this?​