Hi @Ellen Crouch ,
Welcome to our forum!
Are you using Outlook desktop client?
According to your description, I notice that you are sending emails to a group, and you want the first person to reply to the email, and then the second person to reply to the email replied by the first person, repeat the past, right?
If so, as I know, there is no reminder or flag can be set in the mailbox of other recipients in outlook. As a workaround, it's suggested that you could let the recipient choose "Reply All" when replying to the email, and then reply to the reply email of the previous person one by one.
Hope to help you!
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