I've recently been working on a simple-to-use birthday reminder service (simple as in: no need to open any accounts, no need to ever login anywhere, no passwords etc.):
Family has a birthday party supplies business, so there might be some non-intrusive ads for that with the birthday reminders.
Initially the plan was to partner with existing birthday reminder websites, but I didn't like that they required logins, passwords, etc. for something as simple as a birthday reminder.
https://ReminderExpress.com
Just finished working on v1 of this a few minutes ago, by sheer coincidence; it should now be fully functional.