you can subtract no of year it took for approval from the current age..it always better to have a longer wait time as it will protect kids from aging out... example current age of son is 24 u subtract the wait time ... 24-12= 12 years old, I believe ur still safe for few more years..plz remember I am not a immigration lawyer better u seek help from a immigration lawyer for accurate assessment

thank you.

@P David make sure he remains unmarried or else he will not be eligible under F3 with you

@P David did you submit request at USCIS for the case inquiry?