Copy changes on Externals

Hi Guys, I am trying to create a script to copy 2 folders from one external HD to a second one.

The setup is a MBA with an external drive that has the Pictures & Music folders stored on it to free up space on the MBA, i want a 2nd external drive daisy chained and any changes to the Pictures & Music folders on the first drive copied to the second.

The second drive is an off site backup of the Pictures & Music folders.

Is this feasible?

I ended up just using automator and creating a little app to do the rsync for me. All good!