FTP user inside another user

[dzvonyo1]

FTP user inside another user.

what i am trying to achieve is as follows.

I have set-up a website www.test1.com
the directory for www.test1.com is on /var/www/test1

What I need to set now is to have a friend upload(FTP) her photos to my site
but HAVE this friend only access one page where her photos are.

where do i created the directory for her so that she can be able to upload(FTP) her photos,
without changing anything on website.

I tried this
/var/www/test1
mkdir friend
but didn't work.

Thanks