No, but within the next decade, I'm sure one of the 1990s Kenyan or Ethiopian marathoners will have a son run an incredible time.
I think the best the U.S. has is two generations of a family going sub 4:00 in the mile.
Further down the road, since both Ryan Hall and Dathan Ritzenhein married highly talented distance runners, there is the possibility of next generation being exceptional.
On a related thought, I've long been surprised that none of the great NBA big men have had a son who became a great NBA big man. You would have thought that Chamberlain, Russell, Thurmond, Jabbar, Ewing, Olajawon, etc. would have had a son or two, or more in that group that would have been great NBA big men. There wasn't a single one. The great big men of the next generation (O'Neal, Howard, Yao, Oden, etc.) are smaller people's children.