1. One or more computer-readable storage media having instructions stored thereon that, responsive to execution by one or more processors, perform a method comprising: determining a person to which a selected media program has been presented and passive sensor data has been sensed during the presentation of the selected media program to the person; and presenting, in a user interface, an animated avatar performing a media reaction corresponding to a reaction for the person during the presentation of the selected media program to the person, the media reaction determined based on the passive sensor data sensed for the person during the presentation of the selected media program.