I can't honestly speak for Ventura or P & O generally, but I can say that on the three major cruise lines I've sailed with in the past 3 years, internet costs have been breathtakingly expensive. For example, on Celebrity last month they charged $40 for 75 minutes and the connection was painfully slow - it took a good 8 minutes to download email (and that's coming out of the time you've paid for). Shipboard internet connections tend to be slow in general.
Unless she's very rich, I wouldn't advise your daughter to think of using the internet on a ship for any great length of time.
The best option is to use an internet cafe when ashore.......Wilba.
Terminals are available for internet access but the internet cost is very expensive. However, connection to the P&O website is free, within which is the P&O community or forum, where you can communicate to other members free. If you need to email specific persons, get them to join the community and you can then email for free by means of a PM. Many people use this method for keeping in touch with friends and family.