As for your 16-year-old child, he can apply as an accompanying family member together with your elective residence visa application. In this case, the availability of financial resources to be demonstrated must be increased by 5%. His visa and residence permit will have the same validity of yours, so one year, renewable. When he turns 18 years old, he will still be able to renew his permit for family reasons.
Does my son need to apply for a separate visa when he turns 18 if I obtain an elective residence visa of Italy?
I understand that if I obtain an elective residence visa of Italy, my 16-year-old son will be able to join me by applying for a family visa. How long is this visa valid for? Does he lose his eligibility to live in Italy when he turns 18?
When filing the application for the elective residence visa, you can include your children in the application, so that they will also receive an elective residence visa, under the condition that your financial means are considered sufficient for all of you. The visa is valid for one year and must be used to apply for the residence permit that will also have a one-year duration. It is renewable indefinitely with an in-country process. If you do not apply at the same time and your child obtains a permit for family reasons later on, when he turns 18, if he does not study or work, he can renew the permit for family reasons for the same duration of the parents' permit, if the conditions are met.
Minors who hold a family stay permit and who turn 18 while residing in Italy are entitled to have an extension of their family permit. The extension will have the same duration of the stay permit of their parents. After that, they will need to secure their own stay permit. For instance, they can obtain a study permit or a work permit if they find a job in Italy.