Kathy, I'm smiling. I think that is one of the biggest compliments from a mother, to entrust her child to another.
Of course we would be delighted to have your son come visit. They have fantastic youth summer programs here too. Many teenagers travel Germany be "rail", stay in youth hostiles and hike or bike ride in organized groups. My nephew may do that this summer, just using our place as a stop over. Just a thought…I wouldn't want your son to get bored with us oldies.