From advancements in AR to Memojis to group FaceTime, there is plenty to be excited about with iOS 12. But one of the more practical updates to Apple’s mobile operating system, coming this fall, went unmentioned during the keynote at WWDC.

According to 9to5Mac, iOS 12 will allow for two different faces to be registered to Face ID.

Up until now, Face ID has only allowed a single appearance to be registered to the iPhone X. 9to5Mac first noticed the update when combing through the iOS 12 beta, where one can find new settings for Face ID that allow users to “Set Up an Alternative Appearance.”

Here’s what the description says:

In addition to continuously learning how you look, Face ID can recognize an alternative appearance.

While that’s about as unclear as a description might be, 9to5Mac tested and confirmed the update, with the following caveat. Users who choose to register two faces to Face ID will not be able to remove that face without starting over from scratch with their own FaceID registration. In other words, if you choose to reset the alternate appearance, you’ll also have to clear out all existing data around your own face, too.

That small inconvenience aside, the ability to add a second face to Face ID makes total sense. Couples often pass their phones back and forth as a matter of practicality, and parents often let their children use their phones to play games and check out apps.

Plus, this may hint at Face ID on the next generation of iPads, which tend to be shared amongst multiple users more often than phones.