I call bullshit on your "typically" comment. You point to *one* orchestra with a children's program. I live near (well 30 minutes from) and went to UC's College-Conservatory of Music and can tell you it only had a summer program for High School students and even that wasn't called a college orchestra. They called it the Summer Music Institute. And you had to be at least a Junior in high school to attend. How do I know? Cause I went to it my Junior and Senior years.
So *some* may have program's for all ages, but you speak out of your ass when you insist that college orchestras are *typically* for all ages and *most* with a conservatory have them.
Finally, considering *most* schools start teaching musical instruments in 5th grade, his kids, would at a minimum *probably* be at least 13 if they are in a community orchestra (I was in Middletown's Civic Chior and their Community Orchestra throughout sophmore, junior, and senior year and they had an age requirement of 15). So again, he is sheltering them at way to old an age for them to be sheltered.