Need. Training institutions often need to communicate with students' parents about the changes in class hours and campus opening. Notice in the group, some parents and users, because of habit or other reasons, will choose to block or mute the group message, resulting in the notification information not being received in place, and students can not attend classes normally. Therefore, in order to better manage and inform each student, it is necessary for the training institution to send it to parents privately and then inform them.