Syncing POP email between devices
POP is a pretty limited protocol. It doesn't do much beyond getting messages from senders and presenting them to clients (i.e. the iPhone and iPad) as requested. There's no syncing of state (i.e. read messages). Bell, like many major ISPs, only provides POP access, so your options are rather limited.

I would suggest signing your friend up for Gmail, which offers IMAP (and far more storage than Bell). Gmail can be set up check her Bell account, so that all messages to it will funnel into that account. It's even possible to set things up so that messages can be sent by the Bell account via the Gmail account, so that everything appears as it did before to the sender (although I would recommend using the new address as much as possible - it's beneficial to not have an account tied in to your service provider for flexibility).