Dave,

The Language is controlled by the installed operating system. If your sister wants the laptop to work in the English language, than an English version of the Operating system must be installed. I believe that when you buy a new Laptop, at the first use you get the option to install the local language or the English. Also, if she wants to use Office in English, she should buy the English version. Do not install an English version of Office on an Italian OS. The messages will get messed up.

Regards,
Cor