Hi there kamikiller,
It's been a long time. Good to hear from you.
Your Mom should have no problems making a visa application from Italy.
As Ricky has mentioned, it will be a visit to the WorldBridge Visa Application Centre in Rome.
However the application and payment is all done online.
Here's some useful links (be sure to follow all links contained too)
Applying for a UK visa in Italy
Booking an appointment in Italy
Visa application centre in Italy
WorldBridge in Italy Website
There's plenty of posts here on visit visa's and a quick search will likely bring them up.
Just click here on this thread as a good start, I'm sure it will answer most of your questions
I'm sure you know by now that the real keys to getting a visit visa are:-
- Reasons to return home that outweigh reasons to stay in UK
- Financials to support the visit for the complete duration
Good luck.
Don't be shy to ask anything that you need help with.
best regards