I have 2 sons - both love music, but strictly Rock/Rap. They haven't gained an appreciation for Jazz, Classical, or other genre's I listen to. We do share enthusiasm for some rock groups though, and we "steal" each others cd's now and then.
As for equipment, they haven't bought in. Partly because of the money, but I have multiple rooms fitted with pretty decent rigs, and can only be in one at a time - they've never shown an interest in using them. The younger one is probably the most passionate about music, and has the most diverse tastes, but considers my passion (fanaticism?) to be over the top and too time consuming (huh?). He's content to listen to his $100 receiver, with Polk monitors and a Radio Shack subwoofer (gotta have that thump if you're playing Rap). The older one has his BS in Elecrical Engineering now and has shown slight interest in my dedicated listening room. While in college he spent a good deal of time tinkering with his car stereo, including designing/building custom sub enclosures (gotta have that thump), but he hasn't pursued anything "purist" in his own system, though his room system isn't too bad for the money - most of it was gifts from me. He's also a guitar player and now that he's employed with a salary has upgraded his guitar amp and tweeks that now and then.