When he goes his way, a part of you will suffer for it and how could it be otherwise for a father?
But I am sure that he will become a very nice person and he will spend your life and taking his path the pain will be mixed with pride.
We live and give all of ourselves to our children just to prepare them and be ready for the moment they will fly with their wings, to see them go sad but that's what they "worked" for a lifetime.
Did you have a good trip?