Hi fafa123,
Virgin Mobile don't cap accounts but they do give warnings and you can ask her to keep an eye on her usage using the "My Account" app.
Many Android phones can be set to alert the user at a preset limit and can also prevent going over.
Have a look in the settings on her device to see if you restrict the usage this way (although of course you have to trust her to keep them
).
AlexKid :-)
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