Methods, systems, and apparatus, including computer programs encoded on computer storage media, for providing personalized avatars for virtual companionship are disclosed. One of the methods includes capturing one or more current online activities of a user of an online education platform providing learning services to the user; receiving sensor data from one or more electronic devices of the user; detecting an event by analyzing a combination of the one or more captured online activities of the user and the received sensor data; determining one or more avatars and one or more special effects associated with the one or more avatars based on the detected event and one or more pre-determined rules mapping avatars and special effects to events; generating multimedia content comprising the one or more avatars and the one or more special effects; and streaming the generated multimedia content to a multimedia display device of the user.