Good evening, @lynn102918.
Thanks for reaching out here in the Community!
In QuickBooks, there is no built-in feature to send automatic invoice reminders to a different email address other than the standard customer invoicing address.
The email addresses listed on a customer's profile are used for all automated communications, including invoice reminders. The only workaround is to use customer groups for separate statements, or to manually edit and send reminders.
We recommend sending feedback to our Product Developers so they can consider adding this in the near future.
I hope this helps answer your question. If you have any other questions or concerns, don't hesitate to reach back out. Take care!