Yes, if she chooses another speaker.

Insufficient answer and I finally have my system at home!

Correct answer would be "yes, if she chooses another speaker in the Sonos system installed at the same network!“

First off, kind of a rude “thank you”.  Second, you are incorrect.   The speaker she chooses does not need to be on the same Sonos system or network.   It can be same Sonos system on the same network, different system on the same network, or different system on different network.  Same system on different network is not possible.  

If you wanted to play the same audio on different speakers (grouping), then the speakers have to be on the same Sonos system...which has to be on the same network.