Good question dlane26. Take a look at our Check your usage page. If you're set up as the primary line on the account, you can see all the other line's call records through MyT-Mobile.com using the steps on that page.
If you're unsure if you're set up as the primary line (or you don't see the other line listed), give our Customer Care or T-Force a holler either by calling using the number on our Contact Us page or sending a message via the Facebook, Twitter, or Google+ links below. The account will need to be under your name and you will need to be able to verify that account. After that, you can have the representative reference DOC-23157 and it'll guide them through making sure you're set up as the primary number.
How do I access my call records