Några av de senare shortsna visar faktiskt några av händelserna att han besöker henne på natten,
as he's found by Amy in the middle of the night prepping to visit River, showing he does quite literally visit her at night while his companions sleep, meaning the Doctor has twice as many adventures than we normally see. (I guess he doesn't sleep much.) The shorts cover an interlude between between the first date, a middle, and the last that she describes in Forest of the Dead.