we are sort of in the same boat , have a freshman son not very motivated, physician parents, and older child an overachiever (in ivy-level college right now). For him, it is both an issue of not being mature yet, to just not having the personality/intellect like us ( parents) or his older sibling who are overachievers/overcompetitive types – so we have learned to accept him, give him support and realize that he is not going to go to a superselective college, but will still be successful and happy in his chosen field or path.