I did the "add account" wizard under Settings, and when I go under Contacts->Hamburger menu->Contacts to display, a "Yahoo Contacts" option shows up, but none of her contacts are there.

You can manually add new contacts to Yahoo Mail by using the "Add a new contact" feature in the Contacts tab or hovering over the recipient's name.

In addition to releasing a new iOS update, Yahoo today has also released a new version of Yahoo Mail for Android. The update greatly improves the ability to keep track of all of your contacts ...