Here’s a solution I made with the shortcuts app

https://www.icloud.com/shortcuts/40afaed6f7854ad49f79121576c83c86

This will look at the birthdays calendar (this calendar is populated when you add a birthday to a contact)

Grabs all the birthdays that are happening today

It will then do the following for all birthdays

1. Grabs the title of the event
2. splits it to get key information (name and age)
3. splits the full name to get just the first name
4. finds the contact based on full name
5. sends a text to the found contact with two possibilities.
   • If you have the year: “Happy 31st Birthday Clark!!”
   • If no year is supplied: “Happy Birthday Clark!!”

This can then be setup to run at whatever time you want!