Alert Message- Dependents - Employee Central

[Karina9]

Hello,

i am new to EC - client support and i will need your help please with the following situation.

My client wants a alert message to be received per email, every 3 months, once a dependents is being added in the EC SF.

( because every 3 months the dependent needs to provide HR a renewed document ( the document will not be available in the system, that's why we need to set the alert starting from the creation of the dependent in the system)

This alert should be sent every 3 months as long as the dependent is in EC set up.

I have created the alert and workflow, but i need guidance in the business rule.

Also, is it possible to set an alert message once a dependent reaches the age 18 in the system, an alert/warning should be sent?

Thank you in advance for your help and wish you a great day,