If you would like to create a second account for a child or family member using an email address that is already associated with another Duolingo account, you can create an alias email to use for the second account. This works in many email clients such as Gmail, iCloud/Apple, Outlook, and Hotmail, but not all. Please check to see if your email provider supports ‘plus aliasing’ or ‘subaddressing’.
When creating the second account, you will need to type in the alias email address into the email address field for the new account. The alias will need to be formatted with your normal email username first, then add "+aliasname" before @youremail.com. You can use any name or title you would like for the alias. For example, if your e-mail address is myname@gmail.com and you would like the alias to be "duo2", you will need enter the address as myname+duo2@gmail.com. The emails for the second account will still route to your normal inbox.