Currently I am in version 1.0.0-beta.13, near to a project milestone it will very risky to update to the latest ionic version just to check if this was solved there.
I am facing a very similar problem coming from a non-tab view (sign-in view) to a tab view.
Once the user sign-in the app go to the home tab, if the user click a button inside the home tab view the child view inside the same tab gets no back button. This only happen when coming from the sing-in view which is a non-tabbed view.