Constantino Acosta, the four-and-a-half-year-old son of D.C. United midfielder Luciano Acosta, looks a little worried. He’s barely tall enough to see over the ad boards behind the south goal at Audi Field, but midway through the first half of United’s U.S. Open Cup encounter with NYCFC, the youngster has locked his gaze on his father, some 80 yards away.



“Papa! Papa!” he says over and over again, more of a demand than a cheer, as though the youngster expects Acosta, who at the moment is busy fending off a few defenders near the midfield stripe, to play the ball out of bounds and come check on him. “Constantino,” says his mother Carolina. “Ven.”



Her young son pays her no mind. His sister, only a year old, watches on with a baby’s look of amazement. Constantino scampers further down the ad boards at the south end of the stadium to get a better look at the action. Papa is very clearly the center of his universe at the...