Sending SMS & Email reminders on separate dates


Hi, often book patients in for appointments weeks to months ahead. I would like to see a function that enables me to send email reminders to clients 1-2 weeks before the appointment, then a separate SMS reminder 3 days before. This will remind them to contact me to reschedule rather than waiting until they SMS reminder go out so it allows me to fill that spot earlier. A lot of specialists/dentists do this already.