Sharing from our Imac to our MacBook

We have a Mac Book pro and an IMac. I'm an trying to file share between both. When opening both my Itunes account (on the laptop) and my partners itunes account (on the IMac) I can see my Itunes library within the sharing library on the IMac but I am not able to see my partners Itunes account on the laptop. Both have home sharing switched on.

Any thoughts on why? and what I can do to resolve it?

Thanks

Steve