User on my account going to South Africa.

[NewOldcustomer]

New to Verizon as of 8/13.   My mom joined my plan and is traveling to South Africa on 9/27.   She doesn’t need her phone as she is traveling with a group and plans on just using airplane mode.   I told her she can turn WiFi back on.   I have turned settings on the phone to roaming voice only, just in case.  WiFi calling is on.  

I don’t trust iPhones (im an android user) Do I have the option to turn data off on her line as I could on At&t?  If yes, how?

Or will she not have any roaming anyway (At&t doesn’t allow ne accounts to roam for 60 days).