Hi plymtree7. It does sound like an unbalanced wheel/s - although they generally only vibrate in a particular speed range. Has the car clouted a kerb or a pothole as it might have damaged the suspension? It could be a wheel bearing.
I would suggest you get the wheels, bearings and tracking retested. With respect to your son make sure it's someone with the proper laser/mirror or other alignment tools and check they actually do the job! Last year I was charged �29 for tracking adjustment by KwikFit after they fitted new springs and tyres to my Golf. When I drove home the car was all over the road and when I jacked it up I found the track rod adjuster nuts just hadn't been touched! I took the car to ATS and they freed the nuts off and did the tracking. When I returned to Kwik Fit with the receipt the manager didn't argue - he just sheepishly crossed the tracking off the reciept with a pen before opening the till and giving me �29 cash back!
I know your son looked at the car but it may be worth having someone else look as well as something is obvious wrong - and check they actually do the work!