My oldest is 6 years.
But recently I have been helping a buddy refurbish an old shoulder wing model that was flown by his late grandfather back in the early 1970's.
It needs new wing and tail covering to replace the oroginal doped tissue and a repaint of the fuselage. We're also fitting a wing bolt kit to replace the rubber band wing fastening system that's on the model and a set of new lightweight, foam wheels. Other than that its in pretty good shape.