The Schoolmate Tim who recorded my band's demo also opened for the Replacements at 7th St. Entry! "A Few" the rock band

 Tim and Paul Frantzich were songwriters and members of Minneapolis, Minnesota bands A Few (1984–87)

These brothers went to my school and then Tim recorded my band's demo... but I just read (in Peter Jesperson's book) "The Few" also opened for the Replacements at 7th St. Entry for the release of the record Tim.

 wow - small world. 

 https://en.wikipedia.org/wiki/Why_Don%27t_We

His kid formed a top pop boy band...

Jonah Marais Roth Frantzich

https://www.brothertimothy.net/timothy.html 

 https://www.feedthemwithmusic.com/

A music food charity...

 One of their records - the brothers Frantzich

 wow - that one has the new age tenor sax sound. Wow.