Of course.. wouldn't that be fun! My oldest was riding without training wheels at 3.. it should come as no surprise that he's interested in biking with me now that I'm back into it
I personally don't mind investing a bit more in a bike that is more suited to riding "with" me, as well as the fact that if well maintained, can eventually be used for all kids (younger two are 2 and 4.. 4yo isn't even riding with training wheels, but does love her balance bike)